my_userChrome.css not working after update to version 4.5.4

[ChasCB]

Installed the latest version 4.5.4 after using the previous version 4.4.7 since its release.

I have selected all the same @import files as in version 4.4.7 but now find that my own my_userChrome.css not longer operates.

As soon as I switch back to version 4.4.7 all is good again.

[Aris-t2]

Nothing changed for my_userChrome.css inside userChrome.css file for ages.

[ChasCB]

Thank you Aris, all good now. I shouldn't jump to quick.

It took me hours going through my code for the latest release and I finally found the errors. It was a missing closure */ and a miss spelling of a css file after editing because after all these years I have finally edited out all the unwanted code in your release as well as deleting all the unwanted css files. ☹️🤪

Question: Is it advisable to create my own css files from my own my_userChrome code and then merge those new files into your package and do away with my own my_userChrome. Of course I would need to prefix them with:
@import "./css/own/*********.css"; //
I would place this code into a *separate area of your code. LABELLED OWN CODE