How to disable semantic highlighting in lsp-mode?

Question

Language server mode has a variable for semantic highlighting lsp-ht, I would like to disable all syntax highlighting in lsp-mode. Is this possible?

(setq lsp-enable-links nil)
(setq lsp-enable-semantic-highlighting nil)

---

Edit, added an intentional error in ccls which is doing syntax highlithgint to check the call-stack.

Debugger entered--Lisp error: (void-function my-missing-function)
  (save-current-buffer (set-buffer buffer) (my-missing-function) (let* ((modified (buffer-modified-p)) (buffer-undo-list t) (inhibit-read-only t) (inhibit-modification-hooks t)) (unwind-protect (progn (ccls--clear-skipped-ranges) (if ccls-enable-skipped-ranges (progn (overlay-recenter (point-max)) (seq-do #'... (gethash "skippedRanges" params))))) (if modified nil (restore-buffer-modified-p nil)))))
  (progn (save-current-buffer (set-buffer buffer) (my-missing-function) (let* ((modified (buffer-modified-p)) (buffer-undo-list t) (inhibit-read-only t) (inhibit-modification-hooks t)) (unwind-protect (progn (ccls--clear-skipped-ranges) (if ccls-enable-skipped-ranges (progn (overlay-recenter ...) (seq-do ... ...)))) (if modified nil (restore-buffer-modified-p nil))))))
  (if buffer (progn (save-current-buffer (set-buffer buffer) (my-missing-function) (let* ((modified (buffer-modified-p)) (buffer-undo-list t) (inhibit-read-only t) (inhibit-modification-hooks t)) (unwind-protect (progn (ccls--clear-skipped-ranges) (if ccls-enable-skipped-ranges (progn ... ...))) (if modified nil (restore-buffer-modified-p nil)))))))
  (let ((buffer (find-buffer-visiting file))) (if buffer (progn (save-current-buffer (set-buffer buffer) (my-missing-function) (let* ((modified (buffer-modified-p)) (buffer-undo-list t) (inhibit-read-only t) (inhibit-modification-hooks t)) (unwind-protect (progn (ccls--clear-skipped-ranges) (if ccls-enable-skipped-ranges ...)) (if modified nil (restore-buffer-modified-p nil))))))))
  (if file (let ((buffer (find-buffer-visiting file))) (if buffer (progn (save-current-buffer (set-buffer buffer) (my-missing-function) (let* ((modified ...) (buffer-undo-list t) (inhibit-read-only t) (inhibit-modification-hooks t)) (unwind-protect (progn ... ...) (if modified nil ...))))))))
  (let ((file (lsp--uri-to-path (gethash "uri" params)))) (if file (let ((buffer (find-buffer-visiting file))) (if buffer (progn (save-current-buffer (set-buffer buffer) (my-missing-function) (let* (... ... ... ...) (unwind-protect ... ...))))))))
  ccls--publish-skipped-ranges(#s(lsp--workspace :parser #s(lsp--parser :headers (("Content-Length" . "12258")) :body "{\"jsonrpc\":\"2.0\",\"method\":\"$ccls/publishSemanticHi..." :reading-body t :body-length 12258 :body-received 2584 :leftovers nil :workspace #1) :server-capabilities #<hash-table equal 22/22 0x158953e91315> :registered-server-capabilities (#s(lsp--registered-capability :id "didChangeWatchedFiles" :method "workspace/didChangeWatchedFiles" :options #<hash-table equal 1/1 0x158953cad471>)) :root "/src/blender/" :client #s(lsp--client :language-id nil :add-on? nil :new-connection (:connect (closure ((command . #f(compiled-function () #<bytecode 0x158953d94635>)) cl-struct-lsp--log-entry-tags cl-struct-lsp-session-tags cl-struct-lsp--workspace-tags cl-struct-lsp--registered-capability-tags cl-struct-lsp--folding-range-tags cl-struct-lsp-diagnostic-tags cl-struct-lsp-watch-tags cl-struct-lsp--client-tags cl-struct-lsp--parser-tags lsp--log-lines t) (filter sentinel name) (let ((final-command ...) (process-name ...)) (let (...) (set-process-query-on-exit-flag proc nil) (cons proc proc)))) :test\? (closure ((command . #f(compiled-function () #<bytecode 0x158953d94635>)) cl-struct-lsp--log-entry-tags cl-struct-lsp-session-tags cl-struct-lsp--workspace-tags cl-struct-lsp--registered-capability-tags cl-struct-lsp--folding-range-tags cl-struct-lsp-diagnostic-tags cl-struct-lsp-watch-tags cl-struct-lsp--client-tags cl-struct-lsp--parser-tags lsp--log-lines t) nil (lsp-server-present\? (lsp-resolve-final-function command)))) :ignore-regexps nil :ignore-messages nil :notification-handlers #<hash-table equal 2/65 0x158953d94aad> :request-handlers #<hash-table equal 0/65 0x158953d94cdd> :response-handlers #<hash-table eql 0/65 0x158953d94cfd> :prefix-function nil :uri-handlers #<hash-table equal 0/65 0x158953d94d1d> :action-handlers #<hash-table equal 0/65 0x158953d94d3d> :major-modes (c-mode c++-mode cuda-mode objc-mode) :activation-fn nil :priority 0 :server-id ccls :multi-root nil :initialization-options #f(compiled-function () #<bytecode 0x158953d94641>) :library-folders-fn nil :before-file-open-fn nil :initialized-fn nil :remote? nil :completion-in-comments? nil :path->uri-fn nil :uri->path-fn nil) :host-root nil :proc #<process ccls> :cmd-proc #<process ccls> :buffers (#<buffer creator.c>) :highlight-overlays #<hash-table eq 0/65 0x158953bd2cd5> :extra-client-capabilities nil :status initialized :metadata #<hash-table equal 0/65 0x158953bd2e81> :watches #<hash-table equal 0/65 0x158953bd2ea1> :workspace-folders nil :last-id 0 :status-string nil :shutdown-action nil :diagnostics #<hash-table equal 1/65 0x158953bd2ec1> :ewoc nil) #<hash-table equal 2/2 0x158953f46b79>)
  funcall(ccls--publish-skipped-ranges #s(lsp--workspace :parser #s(lsp--parser :headers (("Content-Length" . "12258")) :body "{\"jsonrpc\":\"2.0\",\"method\":\"$ccls/publishSemanticHi..." :reading-body t :body-length 12258 :body-received 2584 :leftovers nil :workspace #2) :server-capabilities #<hash-table equal 22/22 0x158953e91315> :registered-server-capabilities (#s(lsp--registered-capability :id "didChangeWatchedFiles" :method "workspace/didChangeWatchedFiles" :options #<hash-table equal 1/1 0x158953cad471>)) :root "/src/blender/" :client #s(lsp--client :language-id nil :add-on? nil :new-connection (:connect (closure ((command . #f(compiled-function () #<bytecode 0x158953d94635>)) cl-struct-lsp--log-entry-tags cl-struct-lsp-session-tags cl-struct-lsp--workspace-tags cl-struct-lsp--registered-capability-tags cl-struct-lsp--folding-range-tags cl-struct-lsp-diagnostic-tags cl-struct-lsp-watch-tags cl-struct-lsp--client-tags cl-struct-lsp--parser-tags lsp--log-lines t) (filter sentinel name) (let ((final-command ...) (process-name ...)) (let (...) (set-process-query-on-exit-flag proc nil) (cons proc proc)))) :test\? (closure ((command . #f(compiled-function () #<bytecode 0x158953d94635>)) cl-struct-lsp--log-entry-tags cl-struct-lsp-session-tags cl-struct-lsp--workspace-tags cl-struct-lsp--registered-capability-tags cl-struct-lsp--folding-range-tags cl-struct-lsp-diagnostic-tags cl-struct-lsp-watch-tags cl-struct-lsp--client-tags cl-struct-lsp--parser-tags lsp--log-lines t) nil (lsp-server-present\? (lsp-resolve-final-function command)))) :ignore-regexps nil :ignore-messages nil :notification-handlers #<hash-table equal 2/65 0x158953d94aad> :request-handlers #<hash-table equal 0/65 0x158953d94cdd> :response-handlers #<hash-table eql 0/65 0x158953d94cfd> :prefix-function nil :uri-handlers #<hash-table equal 0/65 0x158953d94d1d> :action-handlers #<hash-table equal 0/65 0x158953d94d3d> :major-modes (c-mode c++-mode cuda-mode objc-mode) :activation-fn nil :priority 0 :server-id ccls :multi-root nil :initialization-options #f(compiled-function () #<bytecode 0x158953d94641>) :library-folders-fn nil :before-file-open-fn nil :initialized-fn nil :remote? nil :completion-in-comments? nil :path->uri-fn nil :uri->path-fn nil) :host-root nil :proc #<process ccls> :cmd-proc #<process ccls> :buffers (#<buffer creator.c>) :highlight-overlays #<hash-table eq 0/65 0x158953bd2cd5> :extra-client-capabilities nil :status initialized :metadata #<hash-table equal 0/65 0x158953bd2e81> :watches #<hash-table equal 0/65 0x158953bd2ea1> :workspace-folders nil :last-id 0 :status-string nil :shutdown-action nil :diagnostics #<hash-table equal 1/65 0x158953bd2ec1> :ewoc nil) #<hash-table equal 2/2 0x158953f46b79>)
  (if handler (funcall handler workspace params) (if (string-prefix-p "$" method) nil (lsp-warn "Unknown method: %s" method)))
  (let* ((handler (and t (or (gethash method (progn (or ... ...) (aref client 6))) (gethash method lsp--default-notification-handlers))))) (if handler (funcall handler workspace params) (if (string-prefix-p "$" method) nil (lsp-warn "Unknown method: %s" method))))
  (let* ((params (gethash "params" input0)) (method (gethash "method" input0)) (client input1)) (if lsp-print-io (progn (lsp--log-entry-new (lsp--make-log-entry method nil params 'incoming-notif) lsp--cur-workspace))) (let* ((handler (and t (or (gethash method (progn ... ...)) (gethash method lsp--default-notification-handlers))))) (if handler (funcall handler workspace params) (if (string-prefix-p "$" method) nil (lsp-warn "Unknown method: %s" method)))))
  (let ((input0 notification) (input1 (progn (or (and (memq (type-of workspace) cl-struct-lsp--workspace-tags) t) (signal 'wrong-type-argument (list 'lsp--workspace workspace))) (aref workspace 5)))) (let* ((params (gethash "params" input0)) (method (gethash "method" input0)) (client input1)) (if lsp-print-io (progn (lsp--log-entry-new (lsp--make-log-entry method nil params 'incoming-notif) lsp--cur-workspace))) (let* ((handler (and t (or (gethash method ...) (gethash method lsp--default-notification-handlers))))) (if handler (funcall handler workspace params) (if (string-prefix-p "$" method) nil (lsp-warn "Unknown method: %s" method))))))
  lsp--on-notification(#s(lsp--workspace :parser #s(lsp--parser :headers (("Content-Length" . "12258")) :body "{\"jsonrpc\":\"2.0\",\"method\":\"$ccls/publishSemanticHi..." :reading-body t :body-length 12258 :body-received 2584 :leftovers nil :workspace #1) :server-capabilities #<hash-table equal 22/22 0x158953e91315> :registered-server-capabilities (#s(lsp--registered-capability :id "didChangeWatchedFiles" :method "workspace/didChangeWatchedFiles" :options #<hash-table equal 1/1 0x158953cad471>)) :root "/src/blender/" :client #s(lsp--client :language-id nil :add-on? nil :new-connection (:connect (closure ((command . #f(compiled-function () #<bytecode 0x158953d94635>)) cl-struct-lsp--log-entry-tags cl-struct-lsp-session-tags cl-struct-lsp--workspace-tags cl-struct-lsp--registered-capability-tags cl-struct-lsp--folding-range-tags cl-struct-lsp-diagnostic-tags cl-struct-lsp-watch-tags cl-struct-lsp--client-tags cl-struct-lsp--parser-tags lsp--log-lines t) (filter sentinel name) (let ((final-command ...) (process-name ...)) (let (...) (set-process-query-on-exit-flag proc nil) (cons proc proc)))) :test\? (closure ((command . #f(compiled-function () #<bytecode 0x158953d94635>)) cl-struct-lsp--log-entry-tags cl-struct-lsp-session-tags cl-struct-lsp--workspace-tags cl-struct-lsp--registered-capability-tags cl-struct-lsp--folding-range-tags cl-struct-lsp-diagnostic-tags cl-struct-lsp-watch-tags cl-struct-lsp--client-tags cl-struct-lsp--parser-tags lsp--log-lines t) nil (lsp-server-present\? (lsp-resolve-final-function command)))) :ignore-regexps nil :ignore-messages nil :notification-handlers #<hash-table equal 2/65 0x158953d94aad> :request-handlers #<hash-table equal 0/65 0x158953d94cdd> :response-handlers #<hash-table eql 0/65 0x158953d94cfd> :prefix-function nil :uri-handlers #<hash-table equal 0/65 0x158953d94d1d> :action-handlers #<hash-table equal 0/65 0x158953d94d3d> :major-modes (c-mode c++-mode cuda-mode objc-mode) :activation-fn nil :priority 0 :server-id ccls :multi-root nil :initialization-options #f(compiled-function () #<bytecode 0x158953d94641>) :library-folders-fn nil :before-file-open-fn nil :initialized-fn nil :remote? nil :completion-in-comments? nil :path->uri-fn nil :uri->path-fn nil) :host-root nil :proc #<process ccls> :cmd-proc #<process ccls> :buffers (#<buffer creator.c>) :highlight-overlays #<hash-table eq 0/65 0x158953bd2cd5> :extra-client-capabilities nil :status initialized :metadata #<hash-table equal 0/65 0x158953bd2e81> :watches #<hash-table equal 0/65 0x158953bd2ea1> :workspace-folders nil :last-id 0 :status-string nil :shutdown-action nil :diagnostics #<hash-table equal 1/65 0x158953bd2ec1> :ewoc nil) #<hash-table equal 3/3 0x158953f46b21>)
  (let ((before-notification (current-time))) (lsp--on-notification lsp--cur-workspace json-data) (lsp--log-notification-performance server-id json-data received-time after-parsed-time before-notification (current-time)))
  (cond ((eq val 'response) (progn (or id (cl--assertion-failed 'id)) nil) (let* ((--dash-source-62-- (gethash id (progn (or ... ...) (aref client 8)))) (callback (car-safe (prog1 --dash-source-62-- (setq --dash-source-62-- ...)))) (method (prog1 (car (cdr --dash-source-62--)) (setq --dash-source-62-- (nthcdr 2 --dash-source-62--)))) (start-time (car-safe (prog1 --dash-source-62-- (setq --dash-source-62-- ...)))) (before-send (car --dash-source-62--))) (if lsp-print-io (progn (lsp--log-entry-new (lsp--make-log-entry method id data 'incoming-resp (/ ... 1000)) lsp--cur-workspace))) (if callback (progn (funcall callback (gethash "result" json-data)) (remhash id (progn (or ... ...) (aref client 8))) (lsp--log-request-time server-id method id start-time before-send received-time after-parsed-time (current-time)))))) ((eq val 'response-error) (progn (or id (cl--assertion-failed 'id)) nil) (let* ((--dash-source-64-- (cdr (gethash id (progn ... ...)))) (callback (car-safe (prog1 --dash-source-64-- (setq --dash-source-64-- ...)))) (method (car-safe (prog1 --dash-source-64-- (setq --dash-source-64-- ...)))) (start-time (car-safe (prog1 --dash-source-64-- (setq --dash-source-64-- ...)))) (before-send (car --dash-source-64--))) (if lsp-print-io (progn (lsp--log-entry-new (lsp--make-log-entry method id data 'incoming-resp (/ ... 1000)) lsp--cur-workspace))) (if callback (progn (funcall callback (gethash "error" json-data)) (remhash id (progn (or ... ...) (aref client 8))) (lsp--log-request-time server-id method id start-time before-send received-time after-parsed-time (current-time)))))) ((eq val 'notification) (let ((before-notification (current-time))) (lsp--on-notification lsp--cur-workspace json-data) (lsp--log-notification-performance server-id json-data received-time after-parsed-time before-notification (current-time)))) ((eq val 'request) (lsp--on-request lsp--cur-workspace json-data)) (t nil))
  (let* ((val (lsp--get-message-type json-data))) (cond ((eq val 'response) (progn (or id (cl--assertion-failed 'id)) nil) (let* ((--dash-source-62-- (gethash id (progn ... ...))) (callback (car-safe (prog1 --dash-source-62-- ...))) (method (prog1 (car ...) (setq --dash-source-62-- ...))) (start-time (car-safe (prog1 --dash-source-62-- ...))) (before-send (car --dash-source-62--))) (if lsp-print-io (progn (lsp--log-entry-new (lsp--make-log-entry method id data ... ...) lsp--cur-workspace))) (if callback (progn (funcall callback (gethash "result" json-data)) (remhash id (progn ... ...)) (lsp--log-request-time server-id method id start-time before-send received-time after-parsed-time (current-time)))))) ((eq val 'response-error) (progn (or id (cl--assertion-failed 'id)) nil) (let* ((--dash-source-64-- (cdr (gethash id ...))) (callback (car-safe (prog1 --dash-source-64-- ...))) (method (car-safe (prog1 --dash-source-64-- ...))) (start-time (car-safe (prog1 --dash-source-64-- ...))) (before-send (car --dash-source-64--))) (if lsp-print-io (progn (lsp--log-entry-new (lsp--make-log-entry method id data ... ...) lsp--cur-workspace))) (if callback (progn (funcall callback (gethash "error" json-data)) (remhash id (progn ... ...)) (lsp--log-request-time server-id method id start-time before-send received-time after-parsed-time (current-time)))))) ((eq val 'notification) (let ((before-notification (current-time))) (lsp--on-notification lsp--cur-workspace json-data) (lsp--log-notification-performance server-id json-data received-time after-parsed-time before-notification (current-time)))) ((eq val 'request) (lsp--on-request lsp--cur-workspace json-data)) (t nil)))
  (let* ((client (progn (or (and (memq (type-of lsp--cur-workspace) cl-struct-lsp--workspace-tags) t) (signal 'wrong-type-argument (list 'lsp--workspace lsp--cur-workspace))) (aref lsp--cur-workspace 5))) (received-time (current-time)) (server-id (progn (or (and (memq (type-of client) cl-struct-lsp--client-tags) t) (signal 'wrong-type-argument (list 'lsp--client client))) (aref client 15))) (json-data (lsp--read-json msg)) (after-parsed-time (current-time)) (id (let ((it (gethash "id" json-data))) (if it (progn (if (stringp it) (string-to-number it) it))))) (data (gethash "result" json-data))) (let* ((val (lsp--get-message-type json-data))) (cond ((eq val 'response) (progn (or id (cl--assertion-failed 'id)) nil) (let* ((--dash-source-62-- (gethash id ...)) (callback (car-safe ...)) (method (prog1 ... ...)) (start-time (car-safe ...)) (before-send (car --dash-source-62--))) (if lsp-print-io (progn (lsp--log-entry-new ... lsp--cur-workspace))) (if callback (progn (funcall callback ...) (remhash id ...) (lsp--log-request-time server-id method id start-time before-send received-time after-parsed-time ...))))) ((eq val 'response-error) (progn (or id (cl--assertion-failed 'id)) nil) (let* ((--dash-source-64-- (cdr ...)) (callback (car-safe ...)) (method (car-safe ...)) (start-time (car-safe ...)) (before-send (car --dash-source-64--))) (if lsp-print-io (progn (lsp--log-entry-new ... lsp--cur-workspace))) (if callback (progn (funcall callback ...) (remhash id ...) (lsp--log-request-time server-id method id start-time before-send received-time after-parsed-time ...))))) ((eq val 'notification) (let ((before-notification (current-time))) (lsp--on-notification lsp--cur-workspace json-data) (lsp--log-notification-performance server-id json-data received-time after-parsed-time before-notification (current-time)))) ((eq val 'request) (lsp--on-request lsp--cur-workspace json-data)) (t nil))))
  (let ((lsp--cur-workspace (progn (or (and (memq (type-of p) cl-struct-lsp--parser-tags) t) (signal 'wrong-type-argument (list 'lsp--parser p))) (aref p 7)))) (let* ((client (progn (or (and (memq ... cl-struct-lsp--workspace-tags) t) (signal 'wrong-type-argument (list ... lsp--cur-workspace))) (aref lsp--cur-workspace 5))) (received-time (current-time)) (server-id (progn (or (and (memq ... cl-struct-lsp--client-tags) t) (signal 'wrong-type-argument (list ... client))) (aref client 15))) (json-data (lsp--read-json msg)) (after-parsed-time (current-time)) (id (let ((it (gethash "id" json-data))) (if it (progn (if ... ... it))))) (data (gethash "result" json-data))) (let* ((val (lsp--get-message-type json-data))) (cond ((eq val 'response) (progn (or id (cl--assertion-failed ...)) nil) (let* ((--dash-source-62-- ...) (callback ...) (method ...) (start-time ...) (before-send ...)) (if lsp-print-io (progn ...)) (if callback (progn ... ... ...)))) ((eq val 'response-error) (progn (or id (cl--assertion-failed ...)) nil) (let* ((--dash-source-64-- ...) (callback ...) (method ...) (start-time ...) (before-send ...)) (if lsp-print-io (progn ...)) (if callback (progn ... ... ...)))) ((eq val 'notification) (let ((before-notification ...)) (lsp--on-notification lsp--cur-workspace json-data) (lsp--log-notification-performance server-id json-data received-time after-parsed-time before-notification (current-time)))) ((eq val 'request) (lsp--on-request lsp--cur-workspace json-data)) (t nil)))))
  lsp--parser-on-message(#s(lsp--parser :headers (("Content-Length" . "12258")) :body "{\"jsonrpc\":\"2.0\",\"method\":\"$ccls/publishSemanticHi..." :reading-body t :body-length 12258 :body-received 2584 :leftovers nil :workspace #s(lsp--workspace :parser #1 :server-capabilities #<hash-table equal 22/22 0x158953e91315> :registered-server-capabilities (#s(lsp--registered-capability :id "didChangeWatchedFiles" :method "workspace/didChangeWatchedFiles" :options #<hash-table equal 1/1 0x158953cad471>)) :root "/src/blender/" :client #s(lsp--client :language-id nil :add-on? nil :new-connection (:connect (closure ((command . #f(compiled-function () #<bytecode 0x158953d94635>)) cl-struct-lsp--log-entry-tags cl-struct-lsp-session-tags cl-struct-lsp--workspace-tags cl-struct-lsp--registered-capability-tags cl-struct-lsp--folding-range-tags cl-struct-lsp-diagnostic-tags cl-struct-lsp-watch-tags cl-struct-lsp--client-tags cl-struct-lsp--parser-tags lsp--log-lines t) (filter sentinel name) (let (... ...) (let ... ... ...))) :test\? (closure ((command . #f(compiled-function () #<bytecode 0x158953d94635>)) cl-struct-lsp--log-entry-tags cl-struct-lsp-session-tags cl-struct-lsp--workspace-tags cl-struct-lsp--registered-capability-tags cl-struct-lsp--folding-range-tags cl-struct-lsp-diagnostic-tags cl-struct-lsp-watch-tags cl-struct-lsp--client-tags cl-struct-lsp--parser-tags lsp--log-lines t) nil (lsp-server-present\? (lsp-resolve-final-function command)))) :ignore-regexps nil :ignore-messages nil :notification-handlers #<hash-table equal 2/65 0x158953d94aad> :request-handlers #<hash-table equal 0/65 0x158953d94cdd> :response-handlers #<hash-table eql 0/65 0x158953d94cfd> :prefix-function nil :uri-handlers #<hash-table equal 0/65 0x158953d94d1d> :action-handlers #<hash-table equal 0/65 0x158953d94d3d> :major-modes (c-mode c++-mode cuda-mode objc-mode) :activation-fn nil :priority 0 :server-id ccls :multi-root nil :initialization-options #f(compiled-function () #<bytecode 0x158953d94641>) :library-folders-fn nil :before-file-open-fn nil :initialized-fn nil :remote? nil :completion-in-comments? nil :path->uri-fn nil :uri->path-fn nil) :host-root nil :proc #<process ccls> :cmd-proc #<process ccls> :buffers (#<buffer creator.c>) :highlight-overlays #<hash-table eq 0/65 0x158953bd2cd5> :extra-client-capabilities nil :status initialized :metadata #<hash-table equal 0/65 0x158953bd2e81> :watches #<hash-table equal 0/65 0x158953bd2ea1> :workspace-folders nil :last-id 0 :status-string nil :shutdown-action nil :diagnostics #<hash-table equal 1/65 0x158953bd2ec1> :ewoc nil)) "{\"jsonrpc\":\"2.0\",\"method\":\"$ccls/publishSkippedRan...")
  (let ((m (car --dolist-tail--))) (lsp--parser-on-message p m) (setq --dolist-tail-- (cdr --dolist-tail--)))
  (while --dolist-tail-- (let ((m (car --dolist-tail--))) (lsp--parser-on-message p m) (setq --dolist-tail-- (cdr --dolist-tail--))))
  (let ((--dolist-tail-- messages)) (while --dolist-tail-- (let ((m (car --dolist-tail--))) (lsp--parser-on-message p m) (setq --dolist-tail-- (cdr --dolist-tail--)))))
  (progn (let ((--dolist-tail-- messages)) (while --dolist-tail-- (let ((m (car --dolist-tail--))) (lsp--parser-on-message p m) (setq --dolist-tail-- (cdr --dolist-tail--))))))
  (if messages (progn (let ((--dolist-tail-- messages)) (while --dolist-tail-- (let ((m (car --dolist-tail--))) (lsp--parser-on-message p m) (setq --dolist-tail-- (cdr --dolist-tail--)))))))
  (let ((messages (condition-case err (lsp--parser-read p output) (error (let ((chunk ...)) (lsp--parser-reset p) (ignore (lsp-warn "Failed to parse the following chunk:\n'''\n%s\n'''\nwi..." chunk err))))))) (if messages (progn (let ((--dolist-tail-- messages)) (while --dolist-tail-- (let ((m ...)) (lsp--parser-on-message p m) (setq --dolist-tail-- (cdr --dolist-tail--))))))))
  (progn (let ((messages (condition-case err (lsp--parser-read p output) (error (let (...) (lsp--parser-reset p) (ignore ...)))))) (if messages (progn (let ((--dolist-tail-- messages)) (while --dolist-tail-- (let (...) (lsp--parser-on-message p m) (setq --dolist-tail-- ...))))))))
  (if (let* ((--cl-var-- ignore-regexps) (r nil) (--cl-var-- t) --cl-var--) (while (and (consp --cl-var--) (progn (setq r (car --cl-var--)) (if (string-match r output) (setq --cl-var-- nil --cl-var-- nil) t))) (setq --cl-var-- (cdr --cl-var--))) (if --cl-var-- (progn t) --cl-var--)) (progn (let ((messages (condition-case err (lsp--parser-read p output) (error (let ... ... ...))))) (if messages (progn (let ((--dolist-tail-- messages)) (while --dolist-tail-- (let ... ... ...))))))))
  (closure ((ignore-regexps) (p . #s(lsp--parser :headers (("Content-Length" . "12258")) :body "{\"jsonrpc\":\"2.0\",\"method\":\"$ccls/publishSemanticHi..." :reading-body t :body-length 12258 :body-received 2584 :leftovers nil :workspace #s(lsp--workspace :parser #5 :server-capabilities #<hash-table equal 22/22 0x158953e91315> :registered-server-capabilities (#s(lsp--registered-capability :id "didChangeWatchedFiles" :method "workspace/didChangeWatchedFiles" :options #<hash-table equal 1/1 0x158953cad471>)) :root "/src/blender/" :client #s(lsp--client :language-id nil :add-on? nil :new-connection (:connect ... :test\? ...) :ignore-regexps nil :ignore-messages nil :notification-handlers #<hash-table equal 2/65 0x158953d94aad> :request-handlers #<hash-table equal 0/65 0x158953d94cdd> :response-handlers #<hash-table eql 0/65 0x158953d94cfd> :prefix-function nil :uri-handlers #<hash-table equal 0/65 0x158953d94d1d> :action-handlers #<hash-table equal 0/65 0x158953d94d3d> :major-modes (c-mode c++-mode cuda-mode objc-mode) :activation-fn nil :priority 0 :server-id ccls :multi-root nil :initialization-options #f(compiled-function () #<bytecode 0x158953d94641>) :library-folders-fn nil :before-file-open-fn nil :initialized-fn nil :remote? nil :completion-in-comments? nil :path->uri-fn nil :uri->path-fn nil) :host-root nil :proc #<process ccls> :cmd-proc #<process ccls> :buffers (#<buffer creator.c>) :highlight-overlays #<hash-table eq 0/65 0x158953bd2cd5> :extra-client-capabilities nil :status initialized :metadata #<hash-table equal 0/65 0x158953bd2e81> :watches #<hash-table equal 0/65 0x158953bd2ea1> :workspace-folders nil :last-id 0 :status-string nil :shutdown-action nil :diagnostics #<hash-table equal 1/65 0x158953bd2ec1> :ewoc nil))) cl-struct-lsp--log-entry-tags cl-struct-lsp-session-tags cl-struct-lsp--workspace-tags cl-struct-lsp--registered-capability-tags cl-struct-lsp--folding-range-tags cl-struct-lsp-diagnostic-tags cl-struct-lsp-watch-tags cl-struct-lsp--client-tags cl-struct-lsp--parser-tags lsp--log-lines t) (_proc output) (if (let* ((--cl-var-- ignore-regexps) (r nil) (--cl-var-- t) --cl-var--) (while (and (consp --cl-var--) (progn (setq r ...) (if ... ... t))) (setq --cl-var-- (cdr --cl-var--))) (if --cl-var-- (progn t) --cl-var--)) (progn (let ((messages (condition-case err ... ...))) (if messages (progn (let ... ...)))))))(#<process ccls> "Content-Length: 1463\15\n\15\n{\"jsonrpc\":\"2.0\",\"method\":...")

Answer 1

The ccls semantic highlight is adhoc implementation implemented before the semantic highlight was added to lsp protocol(which FTR is still not in but there is proposal implemented by several language servers). and it is not controlled from lsp-enable-semantic-highlight variable.

To disable it do

(setq  ccls-sem-highlight-method nil)