Bug Description:

Currently, navigation is not supported properly in the 3-way merge editor.

Steps to Reproduce:

1. Open a workspace that has a merge conflict.

2. Click on a file in the Merge Changes section of the Source Control view.

3. Click on the Resolve in Merge Editor button in the bottom right corner of the editor.

4. Go to the end of file in the merge editor's Result pane (to be counted as navigation to a separate location, it needs to be more than 10 lines from the current line) and then Go Back.

Observe that it navigates to another editor for the file instead of staying in the merge editor.

Even worse, it will open more editors for the file (one for each of its base, ours, and theirs versions) if you try to Go Back further in history.

5. Make sure that the file in the merge editor's Result pane contains a symbol definition and a reference to it. Click on the reference and then Go to Definition of it.

Observe that it navigates to another editor for the file instead of staying in the merge editor.

I'll submit a fix soon.

• Operating System: all
• Theia Version: 1.70