This event doesn't disturb me much, but it is far beyond my ken. Here are the facts.
1. Buster could never write from his Linux distros to PLUG because he doesn't remember the password.
2. The password is hidden somewhere on the host Win 10 system.
3. Buster upgraded his guest to the 20's series of Kubuntu by poking about and surprising himself. So after the process he had an up-to-date Kubuntu.
4. One sunny day, a few weeks ago, while in the guest Kubuntu, his mouse drifted across the 'user' space in PLUG, top left on the first page, and the name 'buster' appeared, which he clicked.
5. The password showed up as a series of dots.
6. Ever since, buster has been signed into PLUG in the Kubuntu virtual install.
7. Wonderment to this day.
Sounds like your PLUG password is buried in the Browser, that you are using. You probably could Google for that browser, on how to find what the password is, for the PLUG website.
Here's the problem Bill. While the password is embedded in the Firefox in the host Windows, there is no connection through syncing or a Firefox account to the Firefox in the virtual Kubuntu.
I noticed it shortly after the strange upgrade of Kubuntu I managed to do. So there are two possibilities:
1. The transfer took place during the upgrade, though I have no idea how.
2. The transfer took place by means of magic.