When creating a new post, our users add the images or files (pdf) without any problems.
Now a user has discovered that when he/we want to insert an image "inline" in the text, the library opens in duplicate and also a black box triggers a complete cancellation creation of the post. ("Select from library" has been translated as "Mediathek" in our installation. No changes were made to any code.)
Backdrop 1.23.0 PHP 8.1.7 Firefox 107
Greetings, Heiner
Thanks for reporting this! The multiple instances of the file browser is definitely a bug I've been able to reproduce when "Enable image upload" is turned off. I have reported this in the issue queue. Hopefully someone will look at it soon.
As for the translation - I don't have an answer for this. Is your installation in a language other than English? Is that language selected as default?
As for the black button, that is more likely a bug in the Color module - does your site use that module? Color has been reported to have similar problems in the past. In my opinion, it's best to disable it and just style your site by creating a subtheme and making css changes.