I do not use Spacemacs, but this could be caused by mouse-avoidance-mode. It normally moves the mouse when the cursor is nearby. So it may also apply to tooltips, I am not sure.
You can check if it is enabled with C-h v mouse-avoidance-mode. If it is not nil, you can disable it with (mouse-avoidance-mode -1).
There are also several other options how the ...
Use C-s (company-search-candidates), use C-h f company-search-candidates to learn more:
company-search-candidates is an interactive compiled Lisp function in
Start searching the completion candidates incrementally.
Search can be controlled with the commands:
Spacemacs uses evil-mode which is a VI emulation layer. Evil-mode adds VI modal editing to spacemacs. In a nutshell modal editing has different modes where keybindings do different things. This is partly so that keybindings can remain short and easy to remember.
In essence, the answer to your question is that you enter the space character by switching to ...
If Ctrl-Mouse-1 works well for you, you can always write a function that emulates it's behavior and bind a key to it. If, as you indicate, you want to sync backward to the position in the tex-file corresponding to the beginning of the pdf page, you can emulate a Ctrl-Mouse-1 click on position (1,1) with the function: