JS Syntax Highlighting discards tabs

[ediardo]

Describe the bug
Tabs disappear on JS code blocks

To Reproduce
Steps to reproduce the behavior:

1. Go to https://gist.github.com/ediardo/436cb9e3cfee40b958e8b66a65149809
2. LIne no 2 is indented with tabs. See they disappeared in Kmdr Code block
3. See to original code block. Line no 2 displays the tabs correctly.

Expected behavior
A clear and concise description of what you expected to happen.

Screenshots

Desktop (please complete the following information):

• Version 4.7.12

Additional context
Add any other context about the problem here.