# The #Header markdown syntax stop working

**URL:** https://meta.discourse.org/t/the-header-markdown-syntax-stop-working/67169
**Category:** Support
**Created:** [July 31, 2017, 1:29pm UTC](https://meta.discourse.org/t/the-header-markdown-syntax-stop-working/67169 "2017-07-31T13:29:47Z")
**Posts on this page:** 1
**Showing post:** 2

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### Author: ![david](https://sea3.discourse-cdn.com/meta/user_avatar/meta.discourse.org/david/32/157490_2.png) [@david](https://meta.discourse.org/u/david)
#### Post date: [July 31, 2017, 1:33pm UTC](https://meta.discourse.org/t/the-header-markdown-syntax-stop-working/67169/2 "2017-07-31T13:33:05Z")

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This changed in the migration to commonmark. See here:

> [@CommonMark testing started here!](https://meta.discourse.org/t/commonmark-testing-started-here/65121/78):
>
> I see that headings have changed from ##heading to ## heading (with a space).
> 
> What happens to the old topics that use ##heading instead of ## heading after the upgrade?
> 
> We have to do a remap as describe here [Replace a string in all posts](https://meta.discourse.org/t/replace-a-string-in-all-posts/48729) ?

> [@CommonMark testing started here!](https://meta.discourse.org/t/commonmark-testing-started-here/65121/82):
>
> Very super undecided on a migration script. The concern I have is that it is possible a migration script can mess stuff up more than it will actually help.
> 
> I am semi open to making a script that fixes up bad multiline quotes (one’s that start mid line) and maybe the title thing.
> 
> Will think about it.

> [@CommonMark testing started here!](https://meta.discourse.org/t/commonmark-testing-started-here/65121/84):
>
> No, this is not needed at all. I would not bother. People can fix up the rare affected posts themselves.

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