::: (triple colon) doesnt work on bold rem (won't become list rem)

I’ve noticed a bug where making a rem bold manually (highlight + ctrl-B) and then trying to turn it into a list rem (appending “:::”) doesn’t work.

Repro:

  1. Create rem
  2. Type ::::
  3. it turns to a list properly
  4. Undo so its a regular rem
  5. Highlight the entire rem and make it bold
  6. Type ::: again - nothing happens
  7. Adding newline by hitting enter will also insert a space before the last colon (":: :")
  8. removing the boldness will make it work again