I don't see any limit in the documentation, also it looks like you don't get 'Calculation timed out' error as well so it could be a bug introduced lately. Are you showing it directly or you are using container object. I see Pivot and Straight table options at the top so wondering if its inside a container and if that has some limitations. Just trying to understand things around your problem..
I see similar problem discussed over here, try adding two columns like flags or indicator(need low memory) and delete one column having text of good size, just to check if its really a memory limit issue.
Yeap, you are right, this topic is similar with my issue.
But situation is very weird as I am not even able to delete any column. The system just don't do anything when I try to delete any column.
I tried to delete columns at development server and even on production server (which is more powerful the development server), and at both servers the result is the same - I can't delete columns. 🙄
And it is strange, as 3 months ago I added here new columns and everything was fine, I didn't faced such problems. But after that in the middle of July we updated the Qlik Sense version, and I suppose may be here the cause of problem (new version broke something)...