diff --git a/src/mesa/main/extensions.c b/src/mesa/main/extensions.c
index 21b45915aa0..27f37f73713 100644
--- a/src/mesa/main/extensions.c
+++ b/src/mesa/main/extensions.c
@@ -333,6 +333,14 @@ _mesa_init_extensions(struct gl_extensions *extensions)
 
    /* Then, selectively turn default extensions on. */
    extensions->dummy_true = GL_TRUE;
+
+   /* Always enable these extensions for all drivers.
+    * We can't use dummy_true in extensions_table.h for these
+    * because this would make them non-disablable using
+    * _mesa_override_extensions.
+    */
+   extensions->MESA_pack_invert = GL_TRUE;
+   extensions->MESA_window_pos = GL_TRUE;
 }
 
 
diff --git a/src/mesa/main/extensions_table.h b/src/mesa/main/extensions_table.h
index 940a13be419..e3817f0fb19 100644
--- a/src/mesa/main/extensions_table.h
+++ b/src/mesa/main/extensions_table.h
@@ -371,11 +371,11 @@ EXT(KHR_texture_compression_astc_sliced_3d  , KHR_texture_compression_astc_slice
 
 EXT(MESA_bgra                               , dummy_true                             ,  x ,  x ,  x , ES2, 2021)
 EXT(MESA_framebuffer_flip_y                 , MESA_framebuffer_flip_y                ,  43,  43,  x ,  30, 2018)
-EXT(MESA_pack_invert                        , dummy_true                             , GLL, GLC,  x ,  x , 2002)
+EXT(MESA_pack_invert                        , MESA_pack_invert                       , GLL, GLC,  x ,  x , 2002)
 EXT(MESA_shader_integer_functions           , MESA_shader_integer_functions          , GLL, GLC,  x ,  30, 2016)
 EXT(MESA_texture_signed_rgba                , EXT_texture_snorm                      , GLL, GLC,  x ,  x , 2009)
 EXT(MESA_tile_raster_order                  , MESA_tile_raster_order                 , GLL, GLC,  x , ES2, 2017)
-EXT(MESA_window_pos                         , dummy_true                             , GLL,  x ,  x ,  x , 2000)
+EXT(MESA_window_pos                         , MESA_window_pos                        , GLL,  x ,  x ,  x , 2000)
 EXT(MESA_ycbcr_texture                      , MESA_ycbcr_texture                     , GLL, GLC,  x ,  x , 2002)
 
 EXT(NVX_gpu_memory_info                     , NVX_gpu_memory_info                    , GLL, GLC,  x ,  x , 2013)
diff --git a/src/mesa/main/mtypes.h b/src/mesa/main/mtypes.h
index 17e9deec153..5eb33205fd7 100644
--- a/src/mesa/main/mtypes.h
+++ b/src/mesa/main/mtypes.h
@@ -4565,10 +4565,12 @@ struct gl_extensions
    GLboolean KHR_texture_compression_astc_ldr;
    GLboolean KHR_texture_compression_astc_sliced_3d;
    GLboolean MESA_framebuffer_flip_y;
+   GLboolean MESA_pack_invert;
    GLboolean MESA_tile_raster_order;
    GLboolean EXT_shader_framebuffer_fetch;
    GLboolean EXT_shader_framebuffer_fetch_non_coherent;
    GLboolean MESA_shader_integer_functions;
+   GLboolean MESA_window_pos;
    GLboolean MESA_ycbcr_texture;
    GLboolean NV_alpha_to_coverage_dither_control;
    GLboolean NV_compute_shader_derivatives;