Fix an issue where WinMerge sometimes crashes when executing "Refresh Selected" in the folder compare window. #1120
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
In the current version, WinMerge sometimes crashes when executing "Refresh Selected" in the folder compare window.

In my environment, there is a high probability of a crash, especially if the "Include Subfolders" option is on and many items are selected.
For example, the situation is as shown in the image below. The set of directories compared at this time is attached.
RefreshSelected.zip
As a result of monitoring this phenomenon, the situation when "Refresh Selected" is executed is as follows.
At this time this process may refer to the deleted DiffItem in the compare thread running in parallel.
This PR fixes this issue by performing the UI update process after the process that may delete DiffItems is completed.