When you include an extension within an indented comment, indentation syntax (e.g. `:` or `*`) will get prepended to each line in the comment.
This diff [1] demonstrates this issue. (notice the `::::` at the beginning of each line
This task is about adding support for extensions (e.g. `<syntaxhighlight></syntaxhighlight` and `<math>`</`math>`) within indented comments //before// T246960 is resolved.
=== Actual behavior
1. Go to a talk page where the reply tool is enabled (e.g.https://en.wikipedia.beta.wmflabs.org/wiki/Talk:Cats)
2. Click any "Reply" link
3. Enter the following into the `source` comment area:
```foo
<syntaxhighlight>
bar
baz
</syntaxhighlight>
quux```
4. ⚠️**Notice the following appears in the preview:**
foo
````<syntaxhighlight>
:bar
:baz
:
</syntaxhighlight>```
quux SIGNATURE
5. Click "Reply"
6. ⚠️**Notice the following is posted to the talk page**
foo
````<syntaxhighlight>
:bar
:baz
:
</syntaxhighlight>```
quux SIGNATURE
=== Expected behavior
//@ppelberg to finish writing//
---
1. https://nl.wikipedia.org/w/index.php?title=Overleg_Wikipedia:Discussietools&curid=5351810&diff=56179414&oldid=56109526