Fix for align bone to cursor (missing normalize)

source/blender/editors/armature/armature_edit.c

@@ -296,10 +296,12 @@ static int armature_calc_roll_exec(bContext *C, wmOperator *op)
 				float cursor_rel[3];
 				sub_v3_v3v3(cursor_rel, cursor_local, ebone->head);
 				if (axis_flip) negate_v3(cursor_rel);
+				if (normalize_v3(cursor_rel) != 0.0f) {
 					ebone->roll = ED_rollBoneToVector(ebone, cursor_rel, axis_only);
 				}
 			}
 		}
+	}
 	else if (ELEM(type, CALC_ROLL_TAN_X, CALC_ROLL_TAN_Z)) {
 		for (ebone = arm->edbo->first; ebone; ebone = ebone->next) {
 			if (ebone->parent) {