The gmt6 files are from Nov-2019 to Jul-2020. The gmt_sessions files are from this year (July to Nov).
The files are gmt.* (.canvas .conf .cpt .frame .history .layers.0 .session) which do not exceed 2 KB.
Also there some *.ps- files of some 10- or 100- KB. Rarely a found some bigger eps. There is sometimes some .eps or ps- of some MB. There sr one of 548 MB!! Probably something that went wrong.