Fix high DPI scaling for MATE desktop on Linux (cyberbotics#6261)

* Update webots-linux.sh

* Update changelog-r2023.md

Author: omichel

docs/reference/changelog-r2023.md

@@ -41,6 +41,7 @@ Released on June 27th, 2023.
     - Deprecated the C and MATLAB API functions `wb_supervisor_node_enable/disable_contact_point_tracking` in favor of `wb_supervisor_node_enable/disable_contact_points_tracking` to be more consistent with other APIs ([#5633](https://github.com/cyberbotics/webots/pull/5633)).
     - Remove SUMO dependency from Webots package ([#6245](https://github.com/cyberbotics/webots/pull/6245)).
   - Bug Fixes
+    - Linux: fixed high DPI scaling for MATE desktop ([#6261](https://github.com/cyberbotics/webots/pull/6261)).
     - Windows: fixed conflict with Qt5 installation by removing the `QT_QPA_PLATFORM_PLUGIN_PATH` environment variable from the Webots launcher ([#6258](https://github.com/cyberbotics/webots/pull/6258)).
     - Fixed random crashes while creating [Skin](skin.md) and [Mesh](mesh.md) nodes ([#6218](https://github.com/cyberbotics/webots/pull/6218)).
     - Windows: fixed compilation of controller programs located in paths with non-ASCII characters ([#6235](https://github.com/cyberbotics/webots/pull/6235)).

src/webots/launcher/webots-linux.sh

@@ -79,6 +79,9 @@ if [ "$XDG_CURRENT_DESKTOP" == "i3" ]; then
     export QT_SCALE_FACTOR=2
     export QT_FONT_DPI=80
   fi
+# Fix for MATE desktop
+elif [ "$XDG_CURRENT_DESKTOP" == "MATE" ]; then
+  export QT_ENABLE_HIGHDPI_SCALING=0
 else
   export QT_ENABLE_HIGHDPI_SCALING=1
 fi