I discovered a minor bug in the web based Proton Docs when viewing or editing a document.

I am using an E-reader (specifically [Boox Go color 7]) the device has scroll/page turn buttons used to scroll up & down. The buttons can be configured to [page] or [scroll]. I am using the [scroll] method.
I can scroll down normally, but scroll up doesnt work.

Proton Docs is displayed using Android Firefox on the device, so it is Firefox that is scrolling up & down. There is no issue with this normally on any webpage, but on Proton Docs for some reason I cant scroll up - so I conclude there is some element on the web page which is stopping that action.

I can scroll up & down using finger swipe gesture on the screen & that works OK.
All editing functions seem to work fine.

I realise this is probably an uncommon use case, but Docs on an Ereader is very appropriate.

I also tested this on the Proton Drive android APP. & the pageUP/PageDOWN buttons work as expected.
The app is a bit washed out looking & text looks small on the ereader. But otherwise it functions fine.