the case is that I've created a course in SL360 some time ago (probably late 2019 or early 2020).
Now the course isn't working properly on current version (tested on v3.36.21213.0 and v3.37.21453.0).
Working properly on version v3.33.20697.0 or earlier.
It seems that the problem is connected to a variable displayed on the screen. In the attached file, there are two almost identical slides. They differ only by one text box containing a variable reference. When trying to preview or publish the slide with variable, there seems to be some kind of an error, while the other slide works as expected.