Skip to content

Instantly share code, notes, and snippets.

@chase-moskal

chase-moskal/badtabs.md

Last active July 30, 2025 01:37
Show Gist options

  • Select an option

    Learn more about clone URLs
  • Save chase-moskal/0714c9b5e974f99162774d24524a099a to your computer and use it in GitHub Desktop.

Select an option

Learn more about clone URLs
Save chase-moskal/0714c9b5e974f99162774d24524a099a to your computer and use it in GitHub Desktop.
Download ZIP
demo of a github markdown rendering bug
Raw
badtabs.md

this is a demonstration of a bug in github's markdown rendering with tabs.. in code blocks nested under bullets, lines are rendered with an extra leading space character..

bullet list

  • ❌ yukon 
     alpha
 	alpha
 		alpha
 	alpha
 alpha
    • ❌ british columbia 
       bravo
 	bravo
 		bravo
 	bravo
 bravo

number list

  1. ✅ washington 
    charlie
	charlie
		charlie
	charlie
charlie
    1. ✅ oregon 
      delta
	delta
		delta
	delta
delta

hybrid number/bullet

  1. ✅ baja california 
    echo
	echo
		echo
	echo
echo
    • ❌ sonora 
       foxtrot
 	foxtrot
 		foxtrot
 	foxtrot
 foxtrot
@chase-moskal
Copy link
Author

chase-moskal commented Jul 29, 2025

⚠️ important — this is not just merely an aesthetic problem — when you copy-paste the code, the leading spaces are actually injected into the resulting payload.

said differently, github is actually mangling the code, which will cause syntax errors in some languages.

the code blocks aren't just aesthetically wrong — they are functionally broken.

@ioquatix
Copy link

ioquatix commented Jul 29, 2025

Great visual.

@iwoodroroo
Copy link

iwoodroroo commented Jul 29, 2025

I don't get it

@chase-moskal
Copy link
Author

chase-moskal commented Jul 30, 2025

@iwoodroroo

i'll try to explain this more clearly:

if you are using tabs for indentation in a markdown github readme (which is nice because, with tabs, the indents are now displayed in accordance with the user's own preferences) — the problem is that there is a bug on github, where the text in some codeblocks is actually mangled — unwanted spacebar characters are inserted into the codeblock where none exist in the markdown source — this will cause confusing failures when somebody copy-and-pastes code snippets, because some programming languages require strictly correct indentation.

for more context, see this community discussion, and this one too.

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment