Canvas changed for the worse, now less readable and usable

Since today the canvas is different, narrower, with a width that doesn’t extend beyond a certain amount even by stretching the browser window wider. It shows too few characters per line, therefore to read the code I need to scroll the content right and left (and the horizontal scroll bar is not visible unless I scroll to the bottom of the code). See attached screenshot. The usability of this new canvas is terrible.

Note I haven’t changed anything in my Internet browser nor its setting: Brave running under Ubuntu 24.04.

It looks like the issue got resolved already. The canvas is back to normal.