Document three-way merge for git-to-editor sync

editor/git-essentials.mdx

@@ -67,3 +67,19 @@
 | Create a branch | Create a **branch**, a separate line of work that doesn't affect your live site unless you choose to publish it |
 | Publish on your deployment branch | Push your commit directly, which triggers a deployment |
 | Publish on a feature branch | Create a **pull request**, a proposal to merge your changes into the deployment branch |
+
+## How Git changes sync to the editor
+
+When someone pushes changes to your repository outside the web editor (for example, from a local editor or a merged pull request), the web editor automatically incorporates those changes using a three-way merge.
+
+The merge compares three versions of each affected page:
+
+- **Base**: The last version both the editor and Git agreed on.
+- **Local**: Your current editor content, including any unsaved edits.
+- **Remote**: The newly pushed version from Git.
+
+Changes that don't overlap with your local edits apply automatically. If Git changes and your local edits affect the same part of a page, the editor highlights the conflicting sections so you can decide which version to keep.
+
+<Note>
+  Commits made from the web editor are recognized automatically and do not trigger a sync back into the editor.
+</Note>

editor/publish.mdx

@@ -73,8 +73,15 @@
 Conflicts happen when you try to merge branches with incompatible changes to the same files.
 
 - You and another team member edit the same lines in a file on different branches.
+- Someone pushes changes to your repository that overlap with your unsaved edits in the editor.
 - You move, rename, or delete files on one branch and modify them differently on another branch.
 
+### How the editor handles incoming changes
+
+When changes are pushed to your repository from outside the editor, the editor merges them into your current content automatically. Non-overlapping changes apply without interrupting your work. If incoming changes conflict with your edits, the editor highlights the affected sections so you can review them.
+
+See [How Git changes sync to the editor](/editor/git-essentials#how-git-changes-sync-to-the-editor) for more details on how the merge works.
+
 ### Resolve conflicts
 
 The editor displays warnings when conflicts prevent operations like publishing or switching branches. To resolve conflicts, follow the instructions in the editor to choose which changes to keep.