Looks like a similar issue to what was happening with the nav block before.
When you add a new section, add a heading, and start typing, any spaces added by the space bar get removed after you finish the word.
Only tested in Firefox so far.
EDIT: I believe it might be working fine in Chrome.
Thank you for the report and apologies for the inconvenience.
Indeed, I can confirm this on my side in Firefox, although it seems to have been present before the last update.
We might not be able to get a fix out before tomorrow, I would recommend using another browser in the meantime.
Sorry once again.
Going through the bug reports, I think this was fixed in 188.8.131.52.1.
If you still experience trouble with this issue, I’d be grateful if you could let me know.
Thanks in advance.