One thing is sure
JLIB_DATABASE_ERROR_FUNCTION_FAILED="DB function failed with error number %s <br><span class=\"red\">%s</span>"
And elsewhere, an example

COM_LANGUAGES_N_ITEMS_UNPUBLISHED="%d Content Languages unpublished. <br><strong class=\"red\">Warning!</strong> When using the multilingual functionality (ie when the plugin System - Language Filter is enabled) the Site Default Language also has to be a published Content language."
COM_LANGUAGES_N_ITEMS_UNPUBLISHED_1="Content Language unpublished. <br><strong class=\"red\">Warning!</strong> When using the multilingual functionality (ie when the plugin System - Language Filter is enabled) the Site Default Language also has to be a published Content language."

are a remnant of a former Joomla version where we had a red class. It should be replaced by a simple <strong> and get rid of the span when present.

If you don't, will look at these.

Sorry, I'm a little bit irritated. What are the further plans with all these classes. Will there be hundreds of additional utility classes like .w-1 to .w-250 (1-step-wise) or so or will you add only used classes to scss/css and somebody who makes an override/change has to add custom classes whenever another width like w-89 or so is needed?

Why are there redundant new classes like inline-block. Why not already existing d-inline-block. Reinventing the wheel just because it's BS4 at the moment? BS4 has utilities scss files (e.g. _display.scss) that can be used by template developers even if they don't want to use BS4 in the end.

Or will Joomla provide custom utilies scss files? Also bombed with "!important" rules that are sometimes nice to have, sometimes bothersome?

are a remnant of a former Joomla version where we had a red class. It should be replaced by a simple <strong> and get rid of the span when present.

If you don't, will look at these.

Yes, please do, thank you very much. There are several more styling cases in language strings which you might be able to simplify or to bring in line with the desired development policy. I only changed few such laguage strings (from style=\"color: red"\ to class=\"red\", and the like). It's a kind of legwork that I as an amateur programmer was able to do to help "real developers" of my favorite CMS. :)

Sorry, I'm a little bit irritated. What are the furthor plans with all these classes. Will there be hundreds of additional utility classes like .w-1 to .w-250 (1-step-wise) or so or will you add only used classes to scss/css and somebody who makes an override/change has to add custom classes wherever another width like w-89 or so is needed?

Why are there redundant new classes like inline-block. Why not already existing d-inline-block. Reinventing the wheel just because it's BS4 at the moment? BS4 has utilities scss files (e.g. _display.scss) that can be used by template developers even if they don't want to use BS4 in the end.

Or will Joomla provide custom utilies scss files? Also bombed with "!important" rules that are sometimes nice to have, sometimes bothersome?

@ReLater , I personally just replaced style= with classes. It's a kind of legwork that I, as an amateur programmer, was able to do to help "real developers" of my favorite CMS. :)

Please do correct my overlooks and replace redundant classes with the existing ones. Thank you!

As for more utillity classes, I think this covered them all already, but that's just my guess.

PS. If you know better ways to solve Content-Security-Policy problem (#27297 ), please share!

@chang-zhao it's really appreciated

I'm just asking some questions concerning plans for the further implementation of all these classes in Joomla core PHP and CSS files. Just because it's not clear which ones will be available which one not in the future. Is it allowed to use BS4 classes or will we always provide redundant and new classes. Things like that.

Let's say we add a class w-89 once in a single core file now. Then we decide that it should be w-96, also just used once. Will w-89 then be removed from core (= Atum) css because we don't need it any more or will we have classes in the end that are not used in core...

At the moment we establish also CSS classes in core that are only present in Atum CSS files. "hidden" is a good example. What if I develop my custom backend template? Do I have to search hours for all classes that I need because core PHP are using them or wouldn't it be better to provide an additional "global" scss file that can be used then?

I don't know. That's why I'm asking ;-) Somebody should have a plan if we'll want to get a inconsistent mixture of this and that or... ;-)

@chang-zhao it's really appreciated

I didn't say that it's not.

@chang-zhao Please fix conflicts. Thanks.

Thank you for your contribution! Please test PR #28692.