Currently this differs for the same view-change-keys in different layouts.
When the text is "abc", the size of the key's text changes
when toggling between "123" and "abc"; with the text "ABC",
the size remains about the same.
Part-of: <https://gitlab.gnome.org/World/Phosh/squeekboard/-/merge_requests/611>
A big letter after a small letter looks incorrect on a keyboard,
because that is not normal German grammar and a keyboard is for
inputting text.
The key is also on the left side of the layout,
which makes äÄ not fit the visual flow.
Part-of: <https://gitlab.gnome.org/World/Phosh/squeekboard/-/merge_requests/611>