fix: Compile v8.1.1 instead of latest ffmpeg for Ubuntu, remove override for MainWindow::nativeEvent, and change Windows packages to UCRT.

.github/workflows/ci.yml

@@ -39,7 +39,7 @@ jobs:
       - name: Build FFmpeg from source (Linux)
         if: runner.os == 'Linux'
         run: |
-          git clone --depth 1 https://git.ffmpeg.org/ffmpeg.git ffmpeg-src
+          git clone --branch n8.1.1 --depth 1 https://git.ffmpeg.org/ffmpeg.git ffmpeg-src
           cd ffmpeg-src
           ./configure \
             --prefix="$PWD/../ffmpeg-install" \
@@ -88,21 +88,21 @@ jobs:
         if: runner.os == 'Windows'
         uses: msys2/setup-msys2@v2
         with:
-          msystem: MINGW64
+          msystem: UCRT64
           update: true
           install: >-
-            mingw-w64-x86_64-cmake
-            mingw-w64-x86_64-ninja
-            mingw-w64-x86_64-gcc
-            mingw-w64-x86_64-qt6-base
-            mingw-w64-x86_64-qt6-tools
-            mingw-w64-x86_64-ffmpeg
-            mingw-w64-x86_64-openimageio
-            mingw-w64-x86_64-opencolorio
-            mingw-w64-x86_64-openexr
-            mingw-w64-x86_64-fmt
-            mingw-w64-x86_64-expat
-            mingw-w64-x86_64-portaudio
+            mingw-w64-ucrt-x86_64-cmake
+            mingw-w64-ucrt-x86_64-ninja
+            mingw-w64-ucrt-x86_64-gcc
+            mingw-w64-ucrt-x86_64-qt6-base
+            mingw-w64-ucrt-x86_64-qt6-tools
+            mingw-w64-ucrt-x86_64-ffmpeg
+            mingw-w64-ucrt-x86_64-openimageio
+            mingw-w64-ucrt-x86_64-opencolorio
+            mingw-w64-ucrt-x86_64-openexr
+            mingw-w64-ucrt-x86_64-fmt
+            mingw-w64-ucrt-x86_64-expat
+            mingw-w64-ucrt-x86_64-portaudio
 
       # ------------------------------------------------------------------
       # Configure