It seems that it didn’t work in other versions of Tomee neither.
The problem was having a <c:forEach> in that page (inside a custom component used in that page), even though the commandButton was not inside the loop. By switching to <ui:repeat>, the problem is gone in all versions of Tomee.
It is probably a bug in MyFaces, because Glassfish 126.96.36.199 (with Majorra) doesn’t have this problem. (tested)
So that’s why I wasn’t able to isolate the bug when I tried, because I wasn’t adding a <c:forEach> in the page. Finally!
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