diff --git a/backend/x11/backend.c b/backend/x11/backend.c
index d914ffb1..6faad6df 100644
--- a/backend/x11/backend.c
+++ b/backend/x11/backend.c
@@ -198,6 +198,8 @@ static void backend_destroy(struct wlr_backend *backend) {
 	}
 	wl_list_remove(&x11->display_destroy.link);
 
+	wlr_drm_format_set_finish(&x11->primary_dri3_formats);
+	wlr_drm_format_set_finish(&x11->primary_shm_formats);
 	wlr_drm_format_set_finish(&x11->dri3_formats);
 	wlr_drm_format_set_finish(&x11->shm_formats);
 	free(x11->drm_format);
@@ -658,6 +660,26 @@ struct wlr_backend *wlr_x11_backend_create(struct wl_display *display,
 		return false;
 	}
 
+	// Windows can only display buffers with the depth they were created with
+	// TODO: look into changing the window's depth at runtime
+	const struct wlr_drm_format *dri3_format =
+		wlr_drm_format_set_get(&x11->dri3_formats, x11->x11_format->drm);
+	if (x11->have_dri3 && dri3_format != NULL) {
+		wlr_drm_format_set_add(&x11->primary_dri3_formats,
+			dri3_format->format, DRM_FORMAT_MOD_INVALID);
+		for (size_t i = 0; i < dri3_format->len; i++) {
+			wlr_drm_format_set_add(&x11->primary_dri3_formats,
+				dri3_format->format, dri3_format->modifiers[i]);
+		}
+	}
+
+	const struct wlr_drm_format *shm_format =
+		wlr_drm_format_set_get(&x11->shm_formats, x11->x11_format->drm);
+	if (x11->have_shm && shm_format != NULL) {
+		wlr_drm_format_set_add(&x11->primary_shm_formats,
+			shm_format->format, DRM_FORMAT_MOD_INVALID);
+	}
+
 #if HAS_XCB_ERRORS
 	if (xcb_errors_context_new(x11->xcb, &x11->errors_context) != 0) {
 		wlr_log(WLR_ERROR, "Failed to create error context");
diff --git a/backend/x11/output.c b/backend/x11/output.c
index 56161dee..73266581 100644
--- a/backend/x11/output.c
+++ b/backend/x11/output.c
@@ -23,6 +23,7 @@
 #include "backend/x11.h"
 #include "render/swapchain.h"
 #include "render/wlr_renderer.h"
+#include "types/wlr_buffer.h"
 #include "util/signal.h"
 #include "util/time.h"
 
@@ -514,6 +515,19 @@ static bool output_move_cursor(struct wlr_output *_output, int x, int y) {
 	return true;
 }
 
+static const struct wlr_drm_format_set *output_get_primary_formats(
+		struct wlr_output *wlr_output, uint32_t buffer_caps) {
+	struct wlr_x11_output *output = get_x11_output_from_output(wlr_output);
+	struct wlr_x11_backend *x11 = output->x11;
+
+	if (x11->have_dri3 && (buffer_caps & WLR_BUFFER_CAP_DMABUF)) {
+		return &output->x11->primary_dri3_formats;
+	} else if (x11->have_shm && (buffer_caps & WLR_BUFFER_CAP_SHM)) {
+		return &output->x11->primary_shm_formats;
+	}
+	return NULL;
+}
+
 static const struct wlr_output_impl output_impl = {
 	.destroy = output_destroy,
 	.attach_render = output_attach_render,
@@ -522,6 +536,7 @@ static const struct wlr_output_impl output_impl = {
 	.rollback_render = output_rollback_render,
 	.set_cursor = output_set_cursor,
 	.move_cursor = output_move_cursor,
+	.get_primary_formats = output_get_primary_formats,
 };
 
 struct wlr_output *wlr_x11_output_create(struct wlr_backend *backend) {
diff --git a/include/backend/x11.h b/include/backend/x11.h
index fe818760..bb2bbeb8 100644
--- a/include/backend/x11.h
+++ b/include/backend/x11.h
@@ -91,6 +91,8 @@ struct wlr_x11_backend {
 	struct wlr_drm_format_set dri3_formats;
 	struct wlr_drm_format_set shm_formats;
 	const struct wlr_x11_format *x11_format;
+	struct wlr_drm_format_set primary_dri3_formats;
+	struct wlr_drm_format_set primary_shm_formats;
 	struct wlr_drm_format *drm_format;
 	struct wl_event_source *event_source;