Many thanks for your effort.
As far as mobile devices are concerned, we as the "chief desk" in the forum have not yet given it any thought. This has to do with the subject we are addressing: shortwave radio signals. Most of our users, there aren't that many, use our forum directly in their shack, besides the receiver. Many connect the forum to their radio software and have everything on one device - you only need to switch from one application to the next. But I'll make a note of that for our next "patch day" and install accordingly.
Then what part should I delete from the PHP code?
Too bad that the holidays and recurring events are not displayed. That was quite pleasant with the old "mini-calender" under TP 0.9.x. But well, that's the way it is.
Once again I say thank you very much!