Add disable-cursor-plane debug flag

src/backend/tty.rs

@@ -573,6 +573,13 @@ impl Tty {
             planes.overlay.clear();
         }
 
+        // Cursor planes have bugs on some systems.
+        let cursor_plane_gbm = if config.debug.disable_cursor_plane {
+            None
+        } else {
+            Some(device.gbm.clone())
+        };
+
         let egl_context = device.gles.egl_context();
         let texture_formats = egl_context.dmabuf_texture_formats();
         let render_formats = egl_context.dmabuf_render_formats();
@@ -596,7 +603,7 @@ impl Tty {
             SUPPORTED_COLOR_FORMATS,
             render_formats.clone(),
             device.drm.cursor_size(),
-            Some(device.gbm.clone()),
+            cursor_plane_gbm,
         )?;
 
         let dmabuf_feedback = DmabufFeedbackBuilder::new(device.id, texture_formats.clone())

src/config.rs

@@ -379,6 +379,8 @@ pub struct DebugConfig {
     pub enable_color_transformations_capability: bool,
     #[knuffel(child)]
     pub enable_overlay_planes: bool,
+    #[knuffel(child)]
+    pub disable_cursor_plane: bool,
 }
 
 impl Default for DebugConfig {
@@ -389,6 +391,7 @@ impl Default for DebugConfig {
             wait_for_frame_completion_before_queueing: false,
             enable_color_transformations_capability: false,
             enable_overlay_planes: false,
+            disable_cursor_plane: false,
         }
     }
 }