

The offline version is on izzyondroid.
The design is worse, yes.
I don’t think it matters much because most of the time you only see the autofill thing, not the app.
When you do go to the app, it is to select between multiple credentials, which is still a split second action.
On mobile I have my 2fa in a different more convenient app (aegis), though k2a does allow to copy 2fa codes
The kde default explorer dolphin does.
It creates them at the root of separate partitions (or maybe only network mounts).
Basically as a fallback to moving it slowly into a local trash.
You probably have the system mounted elsewhere and are accessing it remotely with dolphin would be my guess.
Last time I encountered it I found no good solution, it’s very anyoing.
Best workaround is to create a file of the same name as the folder, that way at least it stays empty.