Code block: Some special characters are not escaped when converting to HTML

[ceyhun]

Describe the bug

On web special characters typed inside code block are escaped when converting to HTML. For example:

• < doesn't get converted to <
• [ doesn't get converted to [

This doesn't happen on mobile. And if you try to upload a post with a code block that contains these characters it's not uploaded and the block seems empty on web.

To Reproduce
Steps to reproduce the behavior:

1. Add code block
2. Type <
3. Switch to HTML mode

Expected behavior
Should see < instead of <

Smartphone (please complete the following information):
Same both on iOS and Android

Additional context
If you do the same on web and open the post in mobile you see the escaped characters instead of the characters themselves.