Troubles solved
Bughunting gets really difficult, if you have a lot of GtkWidgets nested and one calculates its size wrong. So finding that little error took longer than implementing the Gtk table calculations into gtk-mui. It's always the last 10%, which take up 90% of the time ;). But now it looks promising:
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Even the page, which was the reason for all the effort, looks now (nearly) perfect:
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You can now do homogeneous and not homogeneous tables, with elements covering more than one cell horizontally or vertically. Tables grow automatically, if you add rows/columns etc. Maybe I should make a custom mui class out of this.. but not now;).
Bughunting gets really difficult, if you have a lot of GtkWidgets nested and one calculates its size wrong. So finding that little error took longer than implementing the Gtk table calculations into gtk-mui. It's always the last 10%, which take up 90% of the time ;). But now it looks promising:

Even the page, which was the reason for all the effort, looks now (nearly) perfect:

You can now do homogeneous and not homogeneous tables, with elements covering more than one cell horizontally or vertically. Tables grow automatically, if you add rows/columns etc. Maybe I should make a custom mui class out of this.. but not now;).