On my PC, the password suggestion list suggests every password from every domain when the username field is automatically pre-filled, instead of the saved password for the username.
When I delete one character, it correctly suggests the matching name and password.
In the little info-bit of your Original Post, above, you wrote:
“Linux Mint Una 20, Brave Version 1.68.128 Chromium: 127.0.6533.73 (Official Build) (64-bit)”
Brave Support needs to know the most recent version of Brave Browser that you are now using.
Please edit/fix up your Original Post and attempt to follow the Brave Support guidelines for submitting a bug report (Official Brave Help Center article):
https://support.brave.com/hc/en-us/articles/360018228951-How-do-I-submit-a-bug-report-
My own suggestions for how to create a bug report, wherein I provide some examples of the steps to take:
Regarding your description of the issue; maybe write that as:
On my Linux OS PC, the Brave Browser’s Password Manager’s password suggestion list, suggests:
every password from every domain when the username field is automatically pre-filled
instead of the saved password for the username.
Writing that, helps the readers of your post, more clearly see the details of your post (IMHO).
And, if you can, change the title of your OP, to only:
Password suggestions don’t match domain or username when username is pre-filled