diff --git a/src/xrt/state_trackers/oxr/oxr_session.c b/src/xrt/state_trackers/oxr/oxr_session.c
index b1ae59065..feada092a 100644
--- a/src/xrt/state_trackers/oxr/oxr_session.c
+++ b/src/xrt/state_trackers/oxr/oxr_session.c
@@ -25,6 +25,7 @@
 #include "util/u_debug.h"
 #include "util/u_misc.h"
 #include "util/u_time.h"
+#include "util/u_verify.h"
 
 #include "math/m_api.h"
 #include "math/m_mathinclude.h"
@@ -1775,7 +1776,6 @@ oxr_session_frame_end(struct oxr_logger *log, struct oxr_session *sess, const Xr
 		return oxr_session_success_result(sess);
 	}
 
-
 	/*
 	 * Blend mode.
 	 * XR_ERROR_ENVIRONMENT_BLEND_MODE_UNSUPPORTED must always be reported,
@@ -1783,16 +1783,16 @@ oxr_session_frame_end(struct oxr_logger *log, struct oxr_session *sess, const Xr
 	 */
 
 	enum xrt_blend_mode blend_mode = oxr_blend_mode_to_xrt(frameEndInfo->environmentBlendMode);
+	struct xrt_device *xdev = GET_XDEV_BY_ROLE(sess->sys, head);
 
-	if (blend_mode == 0) {
+	if (!u_verify_blend_mode_valid(blend_mode)) {
 		return oxr_error(log, XR_ERROR_VALIDATION_FAILURE,
 		                 "(frameEndInfo->environmentBlendMode == "
 		                 "0x%08x) unknown environment blend mode",
 		                 frameEndInfo->environmentBlendMode);
 	}
 
-	struct xrt_device *xdev = GET_XDEV_BY_ROLE(sess->sys, head);
-	if ((blend_mode & xdev->hmd->blend_mode) == 0) {
+	if (!u_verify_blend_mode_supported(xdev, blend_mode)) {
 		//! @todo Make integer print to string.
 		return oxr_error(log, XR_ERROR_ENVIRONMENT_BLEND_MODE_UNSUPPORTED,
 		                 "(frameEndInfo->environmentBlendMode == %u) "
diff --git a/src/xrt/state_trackers/oxr/oxr_system.c b/src/xrt/state_trackers/oxr/oxr_system.c
index 1003cdfab..092702216 100644
--- a/src/xrt/state_trackers/oxr/oxr_system.c
+++ b/src/xrt/state_trackers/oxr/oxr_system.c
@@ -15,6 +15,7 @@
 
 #include "xrt/xrt_device.h"
 #include "util/u_debug.h"
+#include "util/u_verify.h"
 
 #include "oxr_objects.h"
 #include "oxr_logger.h"
@@ -86,6 +87,8 @@ oxr_system_get_by_id(struct oxr_logger *log, struct oxr_instance *inst, XrSystem
 	return XR_SUCCESS;
 }
 
+
+
 XrResult
 oxr_system_fill_in(struct oxr_logger *log, struct oxr_instance *inst, XrSystemId systemId, struct oxr_system *sys)
 {
@@ -151,20 +154,16 @@ oxr_system_fill_in(struct oxr_logger *log, struct oxr_instance *inst, XrSystemId
 
 	struct xrt_device *head = GET_XDEV_BY_ROLE(sys, head);
 
-	uint32_t i = 0;
-	if (head->hmd->blend_mode & XRT_BLEND_MODE_OPAQUE) {
-		sys->blend_modes[i++] = XR_ENVIRONMENT_BLEND_MODE_OPAQUE;
-	}
-	if (head->hmd->blend_mode & XRT_BLEND_MODE_ADDITIVE) {
-		sys->blend_modes[i++] = XR_ENVIRONMENT_BLEND_MODE_ADDITIVE;
-	}
-	if (head->hmd->blend_mode & XRT_BLEND_MODE_ALPHA_BLEND) {
-		sys->blend_modes[i++] = XR_ENVIRONMENT_BLEND_MODE_ALPHA_BLEND;
-	}
-	sys->num_blend_modes = i;
+	assert(head->hmd->num_blend_modes <= XRT_MAX_DEVICE_BLEND_MODES);
+	assert(head->hmd->num_blend_modes != 0);
 
-	assert(i < ARRAY_SIZE(sys->blend_modes));
+	for (size_t i = 0; i < head->hmd->num_blend_modes; i++) {
+		assert(u_verify_blend_mode_valid(head->hmd->blend_modes[i]));
+		sys->blend_modes[i] = (XrEnvironmentBlendMode)head->hmd->blend_modes[i];
+	}
+	sys->num_blend_modes = (uint32_t)head->hmd->num_blend_modes;
 
+	assert(sys->num_blend_modes <= ARRAY_SIZE(sys->blend_modes));
 
 	return XR_SUCCESS;
 }