Why don’t I see some of my edits in revision history?
If you find that you don’t see all of the edits show up in your file’s revision history, it might mean that some of the revisions have been combined because of the file’s size or age, a process known as revision pruning.
What is taking place?
Your edits are tracked as you make them in your file’s revision history so you can see older versions. In some instances, some of these tracked versions can be combined into a single revision in order to save space, a process known as revision pruning. These revisions don’t disappear entirely, as you can see them in the next chronological version of the file that appears in the history.
When would this take place?
File size, as well as the age of a file, are factors in combining revisions. Older revisions are occasionally combined to save space, as are edits in a file where the total amount of storage being used by all of your revisions is nearing the size limit.
Is there a way to permanently save a particular revision?
There is currently no way to save a particular revision within revision history, or retrieve pruned revisions. To permanently save a particular version of a document, spreadsheet, or presentation, go to the File menu and select Make a copy.