 Hi again @mariogrip and @fredldotme!
 
 I debugged the lomiri-ui-toolkit issue. The difference between Qt 5.15.10 and 5.15.12 happens in this line:
 https://gitlab.com/ubports/development/core/lomiri-ui-toolkit/-/blob/1.3.5010/src/LomiriToolkit/ucunits.cpp#L182
 
 In 5.15.10, `nativeInterface` is nullptr. However, in 5.15.12 it's non-null, so `m_gridUnit` is overwritten with a value that doesn't depend on the environment variable, which makes the test fail.
 This is caused by this commit which was first included in 5.15.11:
 https://code.qt.io/cgit/qt/qtbase.git/commit/?id=533fc55d11710069a83fb35aef5ccab576026978
 Oh, in fact there is already an issue about that: https://gitlab.com/ubports/development/core/lomiri-ui-toolkit/-/issues/34