When the user changes the view in the package selector, the view on the left determines the list content on the right. But it doesn't always preselect something, and the selected package on the right doesn't always show something in the "Details" view below.

There used to be a "selectSomething()" function there, but over the decades, this stopped working in some cases. Qt signals might be blocked in some situations, so the signals never arrive.

Check the code for blockSignals() calls or for using a YQSignalBlocker.