These 'themes' are not solely my own creation. Rather, these are pre-configured userChromes based on https://github.com/Aris-t2/CustomCSSforFx & https://github.com/B00ze64/FF-Menu-Icon-Plus-CSS
Having said that, some CSS is unique. So this not entirely reproducable with CustomCSSforFx alone.
Firefox 3 Strata/IE7-inspired Aero theme (UPDATED FOR 91.13): https://mega.nz/file/omp0UYTB#p3FqwtMH43Gi57Lf0Im3WCV7mzqwZ1FTtc_eipHkMhA
Just like the name implies, this is an Aero-theme taken after Firefox 3.x and Internet Explorer 7. It works best with Windows Vista and Windows 7, as well as Windows 8.x provided you use Glass8. May work with Windows 10, expect some caveats.
These themes will ONLY be updated every ESR cycle. At the moment there is a pre-config for both Firefox 78/Waterfox G3, and Firefox 91 (also works in Firefox 102) (..Waterfox G4?) These themes may or may not work with different versions, but I won't support them. Do not report issues outside of 78/91.
You MUST set the color/theme mode to Default in order for the proper Aero/blue color to take effect! There is currently a conflict in Wf G4 with the default Lepton theme used. They're gamers.
Sugegsted tweaks below: