"Fragment has been deleted by another user. Click on "OK" to refresh the document" - clicking OK leads to work loss
Issue description
Users have sometimes found that if they have made changes to a document, and are timed out without having the opportunity to save, then log back in, they receive the message:
Fragment has been deleted by another user. Click on "OK" to refresh the document
When they click ‘OK’, they find that recent changes are cleared.
If users have been making extensive changes over a lengthy period without manually saving, a lot of work can be lost.
Workaround
If you have pressed ‘OK’ and this has removed recent changes, do not save the document.
Instead, do the following:
Go to the project tab for your project.
Open snapshot versions for the document version on which you are working. (You can open Snapshots by pressing the small triangle to the left of the working version name.)
Find the latest Snapshot AUTO-SAVED version (see screenshot below).
Duplicate this version using Actions → 'Duplicate version'.
Continue work in the new version, which should contain your latest changes.

Screenshot of version to be duplicated
Avoiding this problem
We advise that users frequently Save their document to avoid losing extensive changes through issues such as this.
The auto-save function is intended as a backup, but should not be relied upon as the primary means of saving your work.
For more guidance on Saving, including auto-saving and auto-recovery of documents, see Saving your document
Generating PDFs also creates a snapshot version of the document at the time of generating a PDF, which can be used to recover work in the event that an issue causes you to lose your work.