I finally found a way to make the Cinnamon's clock like on Windows which saves a lot of space on the panel and also makes things look better. This how-to is about the Calendar that comes installed by default in Cinnamon. It COULD work with the other calendars that can be installed manually but I've never used them, so IDK for sure.
Right click on the calendar, config, custom date format and enter either one of these:
If you want the time to be centered, add intervals in front of it until it gets to the center. Other ways (such as CSS) simply won't work.

Right click on the calendar, config, custom date format and enter either one of these:
Code:
%H:%M ч. %n %e.%m.%Y - 25.12.2020
%H:%M ч. %n %e %b %Y - 25 дек 2020
If you want the time to be centered, add intervals in front of it until it gets to the center. Other ways (such as CSS) simply won't work.
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