Text is not highlighted in code blocks when using a custom theme

[Oha-you]

Steps to reproduce

1. Add and select a custom Element theme, for example Discord Dark (instructions here)

2. Send a code block

   

3. Either

   • restart Element (a custom theme will be used by default) or
   • switch theme from Dark to a custom one two times

Outcome

What did you expect?

Code stays highlighted with different colors.

What happened instead?

Code is not highlighted. Animation:

Operating system

Windows 10

Application version

Element version 1.9.5

How did you install the app?

From https://element.io/get-started

Homeserver

matrix.org

Will you send logs?

No

[towingie]

up! still annoying

[t3chguy]

@towingie you're welcome to contribute a fix, labs features like custom themes don't really get much attention as they're not used by very many users.