Again I apologize for not answering your question completely.
As for Brave requiring my system password to see stored passwords , …No…, I only have to do that on Windows-7 & Windows-10
I’m thinking, this could be a Linux issue only, As I do not remember having to Edit any stored Logins nor passwords till yesterday.
I have been using Linux Mint for the last 14 months, I installed the 64 Bit Linux version of Brave, once I had Linux fully installed and was able to download. I honestly don’t remember having a need , till yesterday
BTW, I noticed the menue choices are actually “Worded Differently” in Windows & Linux.
Windows has “Copy Password” “Edit Password” where as my screenshot show us “Details” & “Remove”
When I click “Details” a window opens and it provides The URL, Login Name and Password ("…") with again the “EYE” to view the actual password. The window and information in it is “Dead” that is I cannot edit those 3 datum in any way