[Customizing Gitea][PlantUML Integration] instructions not working

[rejuce]

Description

i followed the guide in Customizing Gitea, to add markdown support for plantUML / digaram generation

i added the scripts to the assets, and modofied footer.tmpl as described

i verfied the assets are reachable and the footer.tmpl is refelcted in frontend.

i added an additonal check
console.log("[PlantUML] footer script running; language‑plantuml count =", $('.language-plantuml').length);

which always returns zero even i added to README.md for example a plantuml section as described

@startuml
Alice -> Bob: Hello!
@enduml

which will be rendered also as normal code section. whats missing so it will be actually be picekd up as language-plantuml

Gitea Version

1.24.2

Can you reproduce the bug on the Gitea demo site?

Yes

Log Gist

No response

Screenshots

No response

Git Version

No response

Operating System

No response

How are you running Gitea?

native go in folder

Database

None

[rejuce]

any time later on in browser shell
document.querySelectorAll('pre > code.language-plantuml').length
yiels 1 for example

while at the time the footer script is executed code.language-plantuml')lenght = 0