On 13 Feb 2014, at 0:01, Alan Curtis wrote:
[…] Back to the original problem, changing the Markdown Heading Theme. The only way I could get it to take was to change the font using the menu item View/Font/Show Fonts.
Go to Bundles → Show Bundle Editor… and select Themes → Settings in the list browser.
Here you will see six items named “Markup: Heading «n»”.
The size for the first is set to 2.25em which is 2.25 times larger than the normal font size. Edit that value and click ⌘S to save the change.
The value won’t affect things immidiately due to internal caches. Either relaunch (⌃⌘Q) or change theme for a Markdown file, to see the change.