Solved Things that fill up C:

Update: I've ran the full duration of TreeSize Pro trial. After accounting for all the stuff I mentioned, and in the meantime even installing about 7 years worth of updates via Simplix, I can report that free space amount remains stable :party: Marking as solved!
 

My Computer

Computer type
PC/Desktop
OS
Windows 7 Ultimate x64 (single boot)
Antivirus
Cryptoprevent
Browser
Pale Moon
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