MS Word also used to track changes made to a document, and stored this history in the same file. This was enabled by default, and mainly unknown to the users. Our ministry of transport published a technical feasibility study about the Transrapid, a high-speed train, whether it should be used in Germany or not. The study officially said no. A journalist found out, the study was published in the .doc file format, including the history on changes made. Apparently the document had different numbers before, which could have led to a different result. This change confused some involved parties, which ended up in a scandal. MS later published a tool to remove such history data from their files. Ref1, Ref2, Ref3
The same issue would come up, if you e.g. share files with a client, and a history in this file reveals too much about your computer, text strings, path names... maybe a string somewhere with a folder name "/stupid clients/", or a string indicating one is working for a competitor... PSP seems to store changed text strings in the history by using the identifier 'Characters'. Best to ensure, one does not hand out such histories, and turn off that feature. But how to delete such a history from existing PSP files? Best would be a button, and probably easy to implement. I turned this history off in 2018, but this just means, PSP stops logging future changes - the previously logged data remains in the file. I also tried to find a way to remove the history using a HEX editor, which failed so far. But it showed me, that more than one quarter of the file size of an inspected file was just the history.
But now back to the thread topic!
