Aeromoon, Compact Moon (theme only), Darkness, DarkPitch, Fox 2 The Moon, Littlemoon, Maxi3, Maxi4, MicroMoon, Moonfox3, Moonola, Nauticalia, Noia Moon (theme only), Opresto, PMChrome, PMOpera, Qute Large, Qute Legacy, reinheit, Tangomoon, Tangerinemoon, White Moon and XMoon have been updated. Details for other themes will follow in their respective threads. This is primarily to add full support for Pale Moon 27.3's Permissions Manager, while in many cases improving styling in about:support ("Troubleshooting Information" page) and fixing double "learn more" links in notification popups.
Full details can be find in the changelogs on the respective theme's GitHub repos.
There are some issues with XMoon theme (1.5.1). The theme is picking up background, selection and highlight colors from the system theme, and in some cases these colors may not play so well with the other theme colors.
1. Text is almost unreadable in the menus. So probably theme should define a color for the menu background.
2. Text selection and highlight color in the images below is red-ish (taken from system theme). It should ideally be theme blue.
My Setup: I'm using Numix GTK theme with XFCE desktop environment on Arch Linux. Pale Moon version: 27.1.1
I saw this just before I released, so was able to slip in a quick fix for the main issue here (illegible text). This in particular should be fixed in v1.6.0.
Further research will be required for the selected text styling. Thanks for the report!
For the record though, for the time being I cannot fully support dark system themes in combination with this theme, as it is not yet fully optimised for use on Linux. This will hopefully come in time.