This is not necessarily an obvious fix. The line between content and interface is somewhat blurred with interface added to headings, as the heading text itself is part of the content.

There is already and existing "bug" here in that the section [ edit ] links are shown in the content direction, although because this isn't usually a problem because of the bidi algorithm. If you add a digit to the section edit link, you can see it is rendered incorrectly, e.g. setting to "1 edit" creates:

Another manifestation of this issue is seen with multiple edit links. Here "edit" should be "first" before "edit source", so arguable on the right. Also because the padding is flipped, there is a missing space between the square brackets and the links:

If we set the metadata wrapper to the correct directionality, then the text alignment (correctly changes), but may be considered confusing:

We could set the direction on each metadata item individually:

In T305286#7851931, @Esanders wrote:

We could set the direction on each metadata item individually:

However the buttons are now showing LTR content, but in an RTL order (# of comments is last)
While this looks okay at the moment, because the items are somewhat independent, it is not necessarily always going to work well if our design added any visual connection between the items, or there was some meaning to the order they appeared.

As you noted for the edit links, it may even be desired. If you however want to proceed with the reverse order (by setting the directionality on the wrapper element), what about something along these lines?

:dir(rtl) > .ext-discussiontools-init-section-wrapper-metadata {
	text-align: right;
}
:dir(ltr) > .ext-discussiontools-init-section-wrapper-metadata {
	text-align: left;
}

(In production you would of course use something with slightly better browser support.)

Notes/outcomes from 17 May conversation with @Esanders

1. People are most likely to experience this issue at multi-lingual wikis that default to English (e.g. meta and mediawiki)
2. In line with "1.", I'm removing this task as a blocker to the initial partner wiki deployment
3. There are a series of open questions we'll need to answer before we can address this issue (see ===Open questions in task description)

Change 809728 had a related patch set uploaded (by Bartosz Dziewoński; author: Bartosz Dziewoński):

[mediawiki/extensions/DiscussionTools@master] Use interface language direction for topic metadata wrapper

https://gerrit.wikimedia.org/r/809728

Change 809728 merged by jenkins-bot:

[mediawiki/extensions/DiscussionTools@master] Use interface language direction for topic metadata wrapper

https://gerrit.wikimedia.org/r/809728