diff --git a/player/playloop.c b/player/playloop.c
index c2795e0d40..fc4cfe859e 100644
--- a/player/playloop.c
+++ b/player/playloop.c
@@ -28,6 +28,7 @@
 #include "options/options.h"
 #include "common/common.h"
 #include "common/encode.h"
+#include "options/m_config.h"
 #include "options/m_property.h"
 #include "common/playlist.h"
 #include "input/input.h"
@@ -722,6 +723,14 @@ static void handle_vo_events(struct MPContext *mpctx)
         mp_notify(mpctx, MP_EVENT_WIN_RESIZE, NULL);
     if (events & VO_EVENT_WIN_STATE)
         mp_notify(mpctx, MP_EVENT_WIN_STATE, NULL);
+    if (events & VO_EVENT_FULLSCREEN_STATE) {
+        // The only purpose of this is to update the fullscreen flag on the
+        // playloop side if it changes "from outside" on the VO.
+        int fs = mpctx->opts->vo->fullscreen;
+        vo_control(vo, VOCTRL_GET_FULLSCREEN, &fs);
+        m_config_set_option_raw_direct(mpctx->mconfig,
+            m_config_get_co(mpctx->mconfig, bstr0("fullscreen")), &fs, 0);
+    }
 }
 
 static void handle_sstep(struct MPContext *mpctx)
diff --git a/video/out/vo.h b/video/out/vo.h
index d76329ffeb..5dbdc3fa89 100644
--- a/video/out/vo.h
+++ b/video/out/vo.h
@@ -43,9 +43,12 @@ enum {
     VO_EVENT_AMBIENT_LIGHTING_CHANGED   = 1 << 4,
     // Special mechanism for making resizing with Cocoa react faster
     VO_EVENT_LIVE_RESIZING              = 1 << 5,
+    // Window fullscreen state changed via external influence.
+    VO_EVENT_FULLSCREEN_STATE           = 1 << 6,
 
     // Set of events the player core may be interested in.
-    VO_EVENTS_USER = (VO_EVENT_RESIZE | VO_EVENT_WIN_STATE),
+    VO_EVENTS_USER = VO_EVENT_RESIZE | VO_EVENT_WIN_STATE |
+                     VO_EVENT_FULLSCREEN_STATE,
 };
 
 enum mp_voctrl {
@@ -75,6 +78,8 @@ enum mp_voctrl {
     VOCTRL_BORDER,
     VOCTRL_ALL_WORKSPACES,
 
+    VOCTRL_GET_FULLSCREEN,
+
     VOCTRL_UPDATE_WINDOW_TITLE,         // char*
     VOCTRL_UPDATE_PLAYBACK_STATE,       // struct voctrl_playback_state*
 
diff --git a/video/out/x11_common.c b/video/out/x11_common.c
index 32f5c6c723..46e68d6e71 100644
--- a/video/out/x11_common.c
+++ b/video/out/x11_common.c
@@ -977,17 +977,6 @@ static void vo_x11_update_composition_hint(struct vo *vo)
                     XA_CARDINAL, 32, PropModeReplace, (unsigned char *)&hint, 1);
 }
 
-// Maximally awful hack to get MPOpts.vo.fullscreen set. The awful part is that
-// this sets a variable which is accessed by command.c without synchronization
-// (and which isn't supposed to need any). The need for this is that there's no
-// way to update this flag in any other way at all.
-static void set_global_fs_flag(struct vo *vo, int fs)
-{
-    struct m_config *rootconfig = mp_get_root_config(vo->global);
-    struct MPOpts *opts = rootconfig->optstruct;
-    opts->vo->fullscreen = fs;
-}
-
 static void vo_x11_check_net_wm_state_fullscreen_change(struct vo *vo)
 {
     struct vo_x11_state *x11 = vo->x11;
@@ -1013,7 +1002,7 @@ static void vo_x11_check_net_wm_state_fullscreen_change(struct vo *vo)
         {
             vo->opts->fullscreen = is_fullscreen;
             x11->fs = is_fullscreen;
-            set_global_fs_flag(vo, is_fullscreen);
+            x11->pending_vo_events |= VO_EVENT_FULLSCREEN_STATE;
 
             if (!is_fullscreen && (x11->pos_changed_during_fs ||
                                    x11->size_changed_during_fs))
@@ -1815,6 +1804,9 @@ int vo_x11_control(struct vo *vo, int *events, int request, void *arg)
     case VOCTRL_FULLSCREEN:
         vo_x11_fullscreen(vo);
         return VO_TRUE;
+    case VOCTRL_GET_FULLSCREEN:
+        *(int *)arg = x11->fs;
+        return VO_TRUE;
     case VOCTRL_ONTOP:
         vo_x11_setlayer(vo, opts->ontop);
         return VO_TRUE;