Asterisks have long been replaced by bullets in password fields in most software out there, at least since the Windows XP era. LibreOffice’s authentication dialogs (e.g., Remote Files) still use asterisks though, contributing to an outdated look.
I was reminded of this due to the latest logo update by LastPass, in which they do this exact change due to apparent associations with profanity censoring, something people use asterisks for. 
The Unicode value for the password bullet (from GNOME) is U+2022. This character is well supported in UI fonts from every platform we run on.
OK, a reasonable change.
UX approved, EasyHack proposed.
Not sure if that requires cpp at all. It's a monkey task having a code pointer...
Starting work on this bug. The change is required in vcl/source/control/edit.cxx
Pull request created - https://gerrit.libreoffice.org/#/c/29532/
Ilya Ponamarev committed a patch related to this issue.
It has been pushed to "master":
tdf#102922: Password fields should use u2022 as masking character instead of *
It will be available in 5.3.0.
The patch should be included in the daily builds available at
http://dev-builds.libreoffice.org/daily/ in the next 24-48 hours. More
information about daily builds can be found at:
Affected users are encouraged to test the fix and report feedback.