This happens with kubuntu 23.10 and debian 12 When you look for the free space from diferent UI (dolphin, kde partition, gparter) all shows different data. See video https://drive.google.com/file/d/1FSBt6CCFnd0mJQhaEEhZrCNhj6DRuHJD/view?usp=sharing
Please report this to your distributions or even to the upstream bug trackers of the applications used, and follow their bug reporting rules. Before doing that, please consult the documentation of each of these tools how they might report free space.
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