From 752a42d917d6141178a8a01b71f4eea8b645dcde Mon Sep 17 00:00:00 2001
From: Neil Jenkins <neil@nmjenkins.com>
Date: Wed, 20 Dec 2023 11:13:43 +1100
Subject: [PATCH] Fix Firefox cursor position bug after paste

We merge a faux block with contents from after a split point when
inserting HTML. The merge function presumes this block has already had
fixCursor run on it to ensure we add the <br>s some browsers need to
support correct cursor focusing.

Fixes #451
---
 source/node/MergeSplit.ts    | 7 +++++--
 source/range/InsertDelete.ts | 1 +
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/source/node/MergeSplit.ts b/source/node/MergeSplit.ts
index 0b1a4be..4e8f5fe 100644
--- a/source/node/MergeSplit.ts
+++ b/source/node/MergeSplit.ts
@@ -37,9 +37,12 @@ const fixCursor = (node: Node): Node => {
                 fixer = document.createTextNode('');
             }
         }
-    } else if (node instanceof Element && !node.querySelector('BR')) {
+    } else if (
+        (node instanceof Element || node instanceof DocumentFragment) &&
+        !node.querySelector('BR')
+    ) {
         fixer = createElement('BR');
-        let parent: Element = node;
+        let parent: Element | DocumentFragment = node;
         let child: Element | null;
         while ((child = parent.lastElementChild) && !isInline(child)) {
             parent = child;
diff --git a/source/range/InsertDelete.ts b/source/range/InsertDelete.ts
index 6e0e621..c31c069 100644
--- a/source/range/InsertDelete.ts
+++ b/source/range/InsertDelete.ts
@@ -425,6 +425,7 @@ const insertTreeFragmentIntoRange = (
     // Insert inline content saved from before.
     if (blockContentsAfterSplit && block) {
         const tempRange = range.cloneRange();
+        fixCursor(blockContentsAfterSplit);
         mergeWithBlock(block, blockContentsAfterSplit, tempRange, root);
         range.setEnd(tempRange.endContainer, tempRange.endOffset);
     }