Your WordPress site shows There has been a critical error on this website and most pages are broken, but the home page seems to load.
Why this happens. This error is caused by a known bug in certain versions of PHP. A compiler optimization feature called JIT (Just-In-Time compilation) produces a defective instruction that attempts to allocate roughly 4 gigabytes of memory in a single operation, which immediately crashes the page. The home page may appear to load because it is served from a cached copy, while all non-cached pages fail immediately. This is not caused by your content, any recent changes to your site, or your plugins.
How it is resolved. The fix is a change to the PHP configuration on the server that disables this faulty optimization. Once it is disabled, your site returns to normal with no data or content affected.