I have found that some snippet or autocomplete extensions have this as an unintended consequence. I'm not completely sure, but I think what happens is that the extension does not properly identify the languages which it is used for and it overrides other language support.
From your list, most of those extensions look like they could be the culprit. The extensions for the other languages could also be interfering with HTML files. With 31 extensions, any one of them could be the problem. I'd suggest having different VSCode workspaces for each language/environment and disabling extensions that don't apply to that language to prevent any issues.
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