Clarify extending selection in org-mode

As this question has been asked multiple times, e.g. #110 , adding this note to the FAQ might help other new users in the future.

Author: RKBK

FAQ.org

@@ -24,3 +24,7 @@ Yes, please check out [[https://github.com/Not-Leader/doom-meow][doom meow modul
 *Can I have a major-mode specified local leader?*
 
 No, you can't.  Here is [[https://github.com/meow-edit/meow/pull/126#issuecomment-992004368][the explanation]].
+
+* Why don't the number hints for extending selection show up in org-mode buffers?
+
+The extend selection number hints are disabled in org-mode by default, because they work poorly with variable-width fonts, and fonts with different sizes. If you use a fixed width font and a single font size, the number hints can be enabled in org mode by removing the org symbol from the list meow-expand-exclude-mode-list . See [[https://github.com/meow-edit/meow/issues/110][this issue for more details]].