Privacy Browser Android

[help] surely Clear DOM Storage

When visiting proton.me the login relies on DOM storage to be enabled. After having enabled DOM storage the website functions properly. Without DOM storage the login break's. Now having that DOM storage must be enabled one may expect DOM storage to be in use. After login and use of Proton then I check for Menu > Clear Data > Clear DOM Storage, and see the option is still greyed out. Now, presumably DOM storage would be in use because disabling it breaks proton.me login. Judging by Feature #138 ( https://redmine.stoutner.com/issues/138 ) presumably greyed would be the indicator DOM storage is not in use, although whilst DOM storage is not enabled proton.me login breaks. Is there any way to confirm DOM storage is in use? Does grey indicate DOM storage is not in use: and given the evidence in my use-case is this sure?
I may guess the DOM storage is grey because Proton doesn't access DOM storage using the URL in the browser bar but maybe a subdomian. Why is Clear DOM Storage grey after, presumably, using DOM storage? Is it indicating no DOM storage in use only for the address URL?

I note from "Currently, when clearing DOM Storage using the option menu, the `app_webview/Local Storage` is removed. This will cause DOM Storage to fail until `Clear and Exit` is run." ( https://redmine.stoutner.com/issues/230 ) that Clear and Exit > Clear everything and Clear DOM storage may clear DOM Storage. Is it a sure thing that DOM Storage get's wiped and does not persist on disk after closing? Just making sure that whilst the manual Menu clear is grayed then this couldbe not detecting any DOM storage thus not wiping anything.

1. Does grey indicate DOM storage is not in use?
1a. Given the evidence in my use-case is this sure?
1b. Is Menu > Clear Data > Clear DOM Storage being greyed indicating no DOM storage in use only for the address URL?
2. Does Clear and Exit still clear DOM storage whilst Menu had no indication it was in use?