diff -up firefox-87.0/widget/GfxInfoX11.cpp.firefox-kde-webrender firefox-87.0/widget/GfxInfoX11.cpp
--- firefox-87.0/widget/GfxInfoX11.cpp.firefox-kde-webrender	2021-03-22 19:55:59.169952960 +0100
+++ firefox-87.0/widget/GfxInfoX11.cpp	2021-03-22 20:04:35.332183657 +0100
@@ -738,6 +738,14 @@ const nsTArray<GfxDriverInfo>& GfxInfo::
         DRIVER_GREATER_THAN_OR_EQUAL, V(17, 0, 0, 0),
         "FEATURE_ROLLOUT_INTEL_GNOME_WAYLAND_MESA", "Mesa 17.0.0.0");
 
+    APPEND_TO_DRIVER_BLOCKLIST_EXT(
+        OperatingSystem::Linux, ScreenSizeStatus::All, BatteryStatus::All,
+        DesktopEnvironment::KDE, WindowProtocol::Wayland,
+        DriverVendor::MesaAll, DeviceFamily::IntelRolloutWebRender,
+        nsIGfxInfo::FEATURE_WEBRENDER, nsIGfxInfo::FEATURE_ALLOW_ALWAYS,
+        DRIVER_GREATER_THAN_OR_EQUAL, V(17, 0, 0, 0),
+        "FEATURE_ROLLOUT_INTEL_GNOME_WAYLAND_MESA", "Mesa 17.0.0.0");
+
     // ATI Mesa baseline, chosen arbitrarily.
     APPEND_TO_DRIVER_BLOCKLIST_EXT(
         OperatingSystem::Linux, ScreenSizeStatus::All, BatteryStatus::All,
@@ -754,6 +762,14 @@ const nsTArray<GfxDriverInfo>& GfxInfo::
         DRIVER_GREATER_THAN_OR_EQUAL, V(17, 0, 0, 0),
         "FEATURE_ROLLOUT_ATI_GNOME_WAYLAND_MESA", "Mesa 17.0.0.0");
 
+    APPEND_TO_DRIVER_BLOCKLIST_EXT(
+        OperatingSystem::Linux, ScreenSizeStatus::All, BatteryStatus::All,
+        DesktopEnvironment::KDE, WindowProtocol::Wayland,
+        DriverVendor::MesaAll, DeviceFamily::AtiRolloutWebRender,
+        nsIGfxInfo::FEATURE_WEBRENDER, nsIGfxInfo::FEATURE_ALLOW_ALWAYS,
+        DRIVER_GREATER_THAN_OR_EQUAL, V(17, 0, 0, 0),
+       "FEATURE_ROLLOUT_ATI_GNOME_WAYLAND_MESA", "Mesa 17.0.0.0");
+
 #ifdef EARLY_BETA_OR_EARLIER
     // Intel Mesa baseline, chosen arbitrarily.
     APPEND_TO_DRIVER_BLOCKLIST_EXT(