How to get unique browser binary path identification from PHP?

In a PHP script I want to get a unique browser ID, but not so unique as the user agent ($_SERVER["HTTP_USER_AGENT"]) as the UA changes with every version. I tried removing all numerals in the UA string to evade version dependency, but that has as a side effect that ‘cloned’ browsers like Brave (a Chrome clone) has the same user agent as Chrome itself when omitting digits in the UA string.
I thought that using the browser binary (i.e. like /Applications/Firefox.app/Contents/Resouces/MacOS/Firefox or /usr/bin/firefox) is unique per browser and version independant. But how can I achieve this path (or other unique ID) ?

EDIT: The issue is that I want to get a unique browser ID which is independant on version number but cloned browsers shoud differ from original. So Firefox vs Waterfox or Chrome vs Brave should differ, but Firefox 132 should return the same as Firefox 130.