I use Ubuntu Studio 24.04.2 LTS.
My main ext4 partition (System Files) in Thunar appears as full. But, if I use gnome-disk-utility and/or Gparted, I can see that partition has 5GB free space, at least.
The weird thing is past wesnesday 12, that partition appeared in Thunar with 37 GB free space. I don't have saved any kind of data inside that partition since a month, at least, because all my personal files are recorded inside another partition, which is a NTFS partition.
Also, I had some videos in the home video folder of that partition and I erased all of them, with Thunar. Even the fact those videos aren't there now, there is no changes about the partition status: it still appears as full in Thunar.
Even more, in a terminal I used the line commands to erase all the not necessary files (apt autoremove --purge). The output of that command was not errors, nothing to erase.
So... What's wrong here? Is it a virus? How can I fix this?