The height of the summary element in the following div is added to the padding of the details element every time the details element is toggled.

<div style="min-height:5rem;writing-mode:vertical-rl;background:orange;">
  <details style="padding-bottom:100%;writing-mode:horizontal-tb;width:500px;">
    <summary style="position:relative;height:5rem;cursor:pointer;background:gray;"></summary>
  </details>
</div>

Data URL: data:text/html,<div style="min-height:5rem;writing-mode:vertical-rl;background:orange;"><details style="padding-bottom:100%;writing-mode:horizontal-tb;width:500px;"><summary style="position:relative;height:5rem;cursor:pointer;background:gray;"></summary></details></div>

The problem can be reproduced using a new Firefox profile and is present in Firefox Nightly 109.0a1 (Build ID 20221208153054).

This should be reproducible without <details> as well fwiw.

The severity field is not set for this bug.
:jwatt, could you have a look please?

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For convenience: here's a live version of the testcase that the reporter provided.

(Note: there are some other bugs on file where we've got some unfortunate statefulness with orthogonal flow layout, where one reflow depends on the results of the previous layout [or collapses due to the lack-of-a-previous-layout]; though in most other bugs e.g. bug 1310551, it's scenarios where we get incorrect zero-size measurements on the first layout, rather than dynamically-growing sizes on subsequent relayouts.)