Hi @Sofie
Accepting the changes is completely impossible.
If the Accepting cannot be done, I suggest you copy the document as a backup, then click the "Track Changes“ icon to turn off this feature to have a check. If this action can be finished, you may go to Track Changes Options, uncheck the Options under Show part.
Then save it as a new document, open it and re-turn on "Track Changes“.
Besides, according to the article "Word slows or stops responding if there are excessive tracked changes or comments", it's best to accept or reject tracked changes in the document periodically.
You may also split the document to multiple segments.
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