PWA update weirdness, MIME type error trying to load older, non-existant file

[ssuess]

For a long time now, I have had intermittent errors when updating PWA, and it is always the same symptom. I will get an error along the lines of

Failed to load module script: Expected a JavaScript module script but the server responded with a MIME type of "text/html". Strict MIME type checking is enforced for module scripts per HTML spec.

or

Loading module from “https://my.site.com/app/assets/index.45b2262f.js” was blocked because of a disallowed MIME type (“text/html”).
Loading failed for the module with source “https://my.site.com/app/assets/index.45b2262f.js

The loading failed part is invariably the name of the PREVIOUS version of such a file that existed PRIOR to the PWA update/new files. A force reload will then load the site, but obviously it is less than ideal to tell everywhere to force reload a broken site.

I have this exact same issue whether using apache or nginx.
Yes history mode is enabled (and working except for this) everywhere.
Suspect that this could be related to using a base and start_url for the app that is at /app/ and looking into that. Tried adding the base url to my index.html template (with <base href="<%= pwaManifest.start_url %>/">) as suggested by some threads, but did not help either.
EDIT: I can rule out the start_url/base, i removed it and experience the exact same problem at top level.
Does anyone have any suggestions for fixing or troubleshooting this? Thanks.

[ssuess]

I think I have a workaround, but it worries me a bit. Disabling file hashes seems to resolve the problem (after the second update). I assume this is because my app is no longer looking for a now non existent file, it just tries to load the same name as before. Is this completely safe in terms of caching/invalidating cached files?