PR's often stay open longer than the 8 week auto-close window. After 4 weeks you get this message:

    This pull request has been inactive for more than 4 weeks and will be automatically closed if another 4 weeks passes without any activity. To avoid this, simply add a new comment to the pull request...

People then end up having to add some random, meaningless comment that pollutes the associated mailing list and even leads to misinterpretation, for example: https://github.com/openjdk/jdk/pull/23622#issuecomment-2772607370

Or, to avoid polluting the mailing list, you have to enter an invalid skara command, for example: https://github.com/openjdk/jdk/pull/23683#issuecomment-2805779028

So how about let's create a new skara PR command "/keep-alive" (with alias "/ping") that serves to reset the clock on PR auto-timeouts. Because it's a PR command, it will have the effect of not polluting the mailing list.