Improvement
Fixed-width font support in Markdown-enabled fields
Summary
You can now choose to use a fixed-width font in Markdown-enabled fields, like issue comments and pull request descriptions. Currently these fields use a variable-width font, which can make it…
You can now choose to use a fixed-width font in Markdown-enabled fields, like issue comments and pull request descriptions. Currently these fields use a variable-width font, which can make it difficult to edit advanced Markdown structures like tables and code snippets.
To enable, go to your appearance settings and toggle on Use a fixed-width (monospace) font when editing Markdown in the “Markdown editor font preference” section.
Learn more about writing and formatting on GitHub.
New Releases 
Improvements