Cannot Paste into Password Fields Using Mouse Key Assignments

I am using the Logitech MX Ergo trackball and have assigned the Paste function to one of its keys. It works perfectly everywhere in every app that I use, the only exception being the password fields. Whenever I try using that button in a password field of any application (browsers, PDFs, emails, etc.) I can observe just a single character (dot) being pasted. I can however use CMD+V on the keyboard in the same fields without problems.

I have tried with other programmable mice and I also tried assigning the CMD+V sequence instead of the Paste function, but the problem remains the same. Seems as if MacOS is blocking password pasting with mice keys for some reason.

Anyone knows a way to remove this annoying limitation?