It's not possible to limit how many historical versions of a file SpiderOak ONE keeps or to stop saving them entirely. Historical versions are a critical part of the backup process: If your file is accidentally damaged, you still have the older correct version safely backed up. That being said, you can delete them whenever you feel that you have collected too many.
In the Manage tab of the ONE application on your computer, you will see all of the files you have uploaded to your account. Files which have historical versions will be followed by a number in parentheses which indicates how many historical versions ONE has saved. They will look something like:
To delete any of these historical versions, select the file. A window will slide out from the right displaying all of the file's historical versions, including the date the version was saved and its size. Select any version and then click the Remove button to remove the version from your account. To select multiple versions, hold down the Control key and click which you would like to remove.
Although it is an advanced technique, you can also purge all your historical versions at once by using the command line. For more information on this, see How do I use the --purge-historical-versions option?