if I have an org file like this:
this is [[heading]] * Heading
I can follow "Heading" with 'C-c C-o' so the link and the target are case insensitive.
However if I try to export this org file to html (org-export-to-html) I get this error:
user-error: Unable to resolve link "heading"
which means that for html exporter the link and the target are case sensitive. Is there a way to make it case insensitive?