I noticed that the developer of kitty terminal uses this style of comments I have rarely if ever seen elsewhere:

outside
#: section {{{
inside
#: }}}

Kate text editor recognize sections for purposes of highlighting, folding etc. It's really nice for me because I sometimes I have a difficult time navigating large text files. And it lets you nest them.

• what is this called?
• are there other ways to do it?
• is it standard among text editors? I believe Kovid the dev for kitty is a vim guy so presumably there is support there also.
• why don't more people use it? are there problems?

Screenshot that shows the code folding.

• Cursor is at the end of line 7 so the whole section line 7-22 is highlighted
• lines 12-16 are folded in a 3rd level comment
• I also included tab indents just to make it easier to see what's going on (Kate treats it the same way regardless of indents)
• Highlighting/Mode > Scripts > Bash

I also like his style of distinguishing between narrative comments (starting with #:) and commented-out code (starting with #). Although in my example, Kate doesn't treat them differently. Is there a term for this? Any conventions, support etc?

#: Comment level 1 {{{
	#: Comment level 2 {{{
		#: configure something
		key value
	#: }}}
	#: Another Comment level 2 {{{
		#: Comment level 3 {{{
			#: Helpful explanatory comment
			file location
		#: }}}
		#: Comment level 3 with hidden text {{{
			you_cant see_this
			hidden_emoji "👁️"
			hidden_emoji2 " 👁️"
			hidden_emoji3 "   👁️"
		#: }}}
		#: let's set some things up
		# setting yes
		# other_setting no
		different_setting maybe
	#: }}}
	# regular comment
#: }}}

# regular comment outside anything

For a real world example, see sample kitty.conf file provided on project website.