diff --git a/.gitignore b/.gitignore
index cab03277..caa3b22e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -12,6 +12,8 @@ stamp-h1
 compton
 *.o
 build/
+compile_commands.json
+build.ninja
 
 # CMake files
 compton-*.deb
@@ -45,3 +47,4 @@ doxygen/
 .ycm_extra_conf.pyc
 /src/backtrace-symbols.[ch]
 /compton*.trace
+*.orig
diff --git a/compton.sample.conf b/compton.sample.conf
index bc6ad51a..024a7aff 100644
--- a/compton.sample.conf
+++ b/compton.sample.conf
@@ -77,8 +77,6 @@ invert-color-include = [ ];
 # glx-no-rebind-pixmap = true;
 glx-swap-method = "undefined";
 # glx-use-gpushader4 = true;
-# xrender-sync = true;
-# xrender-sync-fence = true;
 
 # Window type settings
 wintypes:
diff --git a/man/compton.1.asciidoc b/man/compton.1.asciidoc
index dd896814..5dc2fd7b 100644
--- a/man/compton.1.asciidoc
+++ b/man/compton.1.asciidoc
@@ -242,7 +242,7 @@ May also be one of the predefined kernels: `3x3box` (default), `5x5box`, `7x7box
 +
 --
 * `xrender` backend performs all rendering operations with X Render extension. It is what `xcompmgr` uses, and is generally a safe fallback when you encounter rendering artifacts or instability.
-* `glx` (OpenGL) backend performs all rendering operations with OpenGL. It is more friendly to some VSync methods, and has significantly superior performance on color inversion (`--invert-color-include`) or blur (`--blur-background`). It requires proper OpenGL 2.0 support from your driver and hardware. You may wish to look at the GLX performance optimization options below. `--xrender-sync` and `--xrender-sync-fence` might be needed on some systems to avoid delay in changes of screen contents.
+* `glx` (OpenGL) backend performs all rendering operations with OpenGL. It is more friendly to some VSync methods, and has significantly superior performance on color inversion (`--invert-color-include`) or blur (`--blur-background`). It requires proper OpenGL 2.0 support from your driver and hardware. You may wish to look at the GLX performance optimization options below.
 * `xr_glx_hybrid` backend renders the updated screen contents with X Render and presents it on the screen with GLX. It attempts to address the rendering issues some users encountered with GLX backend and enables the better VSync of GLX backends. `--vsync-use-glfinish` might fix some rendering issues with this backend.
 --
 
@@ -258,12 +258,6 @@ May also be one of the predefined kernels: `3x3box` (default), `5x5box`, `7x7box
 *--glx-use-gpushader4*::
 	GLX backend: Use 'GL_EXT_gpu_shader4' for some optimization on blur GLSL code. My tests on GTX 670 show no noticeable effect.
 
-*--xrender-sync*::
-	Attempt to synchronize client applications' draw calls with `XSync()`, used on GLX backend to ensure up-to-date window content is painted.
-
-*--xrender-sync-fence*::
-	Additionally use X Sync fence to sync clients' draw calls. Needed on nvidia-drivers with GLX backend for some users. May be disabled at compile time with `NO_XSYNC=1`.
-
 *--glx-fshader-win* 'SHADER'::
 	GLX backend: Use specified GLSL fragment shader for rendering window contents. See `compton-default-fshader-win.glsl` and `compton-fake-transparency-fshader-win.glsl` in the source tree for examples.
 
diff --git a/src/common.h b/src/common.h
index 29d40fae..8c64401b 100644
--- a/src/common.h
+++ b/src/common.h
@@ -49,14 +49,6 @@
 // #define CONFIG_OPENGL 1
 // Whether to enable DBus support with libdbus.
 // #define CONFIG_DBUS 1
-// Whether to enable X Sync support.
-// #define CONFIG_XSYNC 1
-// Whether to enable GLX Sync support.
-// #define CONFIG_GLX_XSYNC 1
-
-#if (!defined(CONFIG_XSYNC) || !defined(CONFIG_OPENGL)) && defined(CONFIG_GLX_SYNC)
-#error Cannot enable GL sync without X Sync / OpenGL support.
-#endif
 
 #ifndef COMPTON_VERSION
 #define COMPTON_VERSION "unknown"
@@ -82,9 +74,6 @@
 
 #include <X11/Xlib-xcb.h>
 #include <X11/Xlib.h>
-#ifdef CONFIG_XSYNC
-#include <X11/extensions/sync.h>
-#endif
 
 #include <xcb/composite.h>
 #include <xcb/render.h>
@@ -460,11 +449,6 @@ typedef struct options_t {
   char *display_repr;
   /// The backend in use.
   enum backend backend;
-  /// Whether to sync X drawing to avoid certain delay issues with
-  /// GLX backend.
-  bool xrender_sync;
-  /// Whether to sync X drawing with X Sync fence.
-  bool xrender_sync_fence;
   /// Whether to avoid using stencil buffer under GLX backend. Might be
   /// unsafe.
   bool glx_no_stencil;
@@ -740,9 +724,6 @@ typedef struct session {
   xcb_render_picture_t tgt_picture;
   /// Temporary buffer to paint to before sending to display.
   paint_t tgt_buffer;
-#ifdef CONFIG_XSYNC
-  XSyncFence tgt_buffer_fence;
-#endif
   /// Window ID of the window we register as a symbol.
   Window reg_win;
 #ifdef CONFIG_OPENGL
@@ -904,14 +885,6 @@ typedef struct session {
   region_t *xinerama_scr_regs;
   /// Number of Xinerama screens.
   int xinerama_nscrs;
-#endif
-#ifdef CONFIG_XSYNC
-  /// Whether X Sync extension exists.
-  bool xsync_exists;
-  /// Event base number for X Sync extension.
-  int xsync_event;
-  /// Error base number for X Sync extension.
-  int xsync_error;
 #endif
   /// Whether X Render convolution filter exists.
   bool xrfilter_convolution_exists;
@@ -1491,20 +1464,6 @@ free_all_damage_last(session_t *ps) {
     pixman_region32_clear(&ps->all_damage_last[i]);
 }
 
-#ifdef CONFIG_XSYNC
-/**
- * Free a XSync fence.
- */
-static inline void
-free_fence(session_t *ps, XSyncFence *pfence) {
-  if (*pfence)
-    XSyncDestroyFence(ps->dpy, *pfence);
-  *pfence = None;
-}
-#else
-#define free_fence(ps, pfence) ((void) 0)
-#endif
-
 /**
  * Check if a rectangle includes the whole screen.
  */
@@ -1743,60 +1702,6 @@ glx_mark_frame(session_t *ps) {
 
 ///@}
 
-#ifdef CONFIG_XSYNC
-#define xr_sync(ps, d, pfence) xr_sync_(ps, d, pfence)
-#else
-#define xr_sync(ps, d, pfence) xr_sync_(ps, d)
-#endif
-
-/**
- * Synchronizes a X Render drawable to ensure all pending painting requests
- * are completed.
- */
-static inline void
-xr_sync_(session_t *ps, Drawable d
-#ifdef CONFIG_XSYNC
-    , XSyncFence *pfence
-#endif
-    ) {
-  if (!ps->o.xrender_sync)
-    return;
-
-  x_sync(ps->c);
-#ifdef CONFIG_XSYNC
-  if (ps->o.xrender_sync_fence && ps->xsync_exists) {
-    // TODO: If everybody just follows the rules stated in X Sync prototype,
-    // we need only one fence per screen, but let's stay a bit cautious right
-    // now
-    XSyncFence tmp_fence = None;
-    if (!pfence)
-      pfence = &tmp_fence;
-    assert(pfence);
-    if (!*pfence)
-      *pfence = XSyncCreateFence(ps->dpy, d, False);
-    if (*pfence) {
-      Bool __attribute__((unused)) triggered = False;
-      /* if (XSyncQueryFence(ps->dpy, *pfence, &triggered) && triggered)
-        XSyncResetFence(ps->dpy, *pfence); */
-      // The fence may fail to be created (e.g. because of died drawable)
-      assert(!XSyncQueryFence(ps->dpy, *pfence, &triggered) || !triggered);
-      XSyncTriggerFence(ps->dpy, *pfence);
-      XSyncAwaitFence(ps->dpy, pfence, 1);
-      assert(!XSyncQueryFence(ps->dpy, *pfence, &triggered) || triggered);
-    }
-    else {
-      printf_errf("(%#010lx): Failed to create X Sync fence.", d);
-    }
-    free_fence(ps, &tmp_fence);
-    if (*pfence)
-      XSyncResetFence(ps->dpy, *pfence);
-  }
-#endif
-#ifdef CONFIG_GLX_SYNC
-  xr_glx_sync(ps, d, pfence);
-#endif
-}
-
 /** @name DBus handling
  */
 ///@{
diff --git a/src/compton.c b/src/compton.c
index 9b7dfaca..c9b3606f 100644
--- a/src/compton.c
+++ b/src/compton.c
@@ -701,9 +701,6 @@ win_build_shadow(session_t *ps, win *w, double opacity) {
   assert(!w->shadow_paint.pict);
   w->shadow_paint.pict = shadow_picture_argb;
 
-  // Sync it once and only once
-  xr_sync(ps, w->shadow_paint.pixmap, NULL);
-
   xcb_free_gc(ps->c, gc);
   xcb_image_destroy(shadow_image);
   xcb_free_pixmap(ps->c, shadow_pixmap);
@@ -1445,8 +1442,6 @@ paint_one(session_t *ps, win *w, const region_t *reg_paint) {
     w->paint.pixmap = xcb_generate_id(ps->c);
     set_ignore_cookie(ps,
         xcb_composite_name_window_pixmap(ps->c, w->id, w->paint.pixmap));
-    if (w->paint.pixmap)
-      free_fence(ps, &w->fence);
   }
 
   Drawable draw = w->paint.pixmap;
@@ -1463,9 +1458,6 @@ paint_one(session_t *ps, win *w, const region_t *reg_paint) {
         draw, XCB_RENDER_CP_SUBWINDOW_MODE, &pa);
   }
 
-  if (IsViewable == w->a.map_state)
-    xr_sync(ps, draw, &w->fence);
-
   // GLX: Build texture
   // Let glx_bind_pixmap() determine pixmap size, because if the user
   // is resizing windows, the width and height we get may not be up-to-date,
@@ -1846,12 +1838,9 @@ paint_all(session_t *ps, region_t *region, const region_t *region_real, win * co
         glFlush();
       glXWaitX();
       assert(ps->tgt_buffer.pixmap);
-      xr_sync(ps, ps->tgt_buffer.pixmap, &ps->tgt_buffer_fence);
       paint_bind_tex(ps, &ps->tgt_buffer,
           ps->root_width, ps->root_height, ps->depth,
           !ps->o.glx_no_rebind_pixmap);
-      // See #163
-      xr_sync(ps, ps->tgt_buffer.pixmap, &ps->tgt_buffer_fence);
       if (ps->o.vsync_use_glfinish)
         glFinish();
       else
@@ -2079,11 +2068,6 @@ unmap_win(session_t *ps, win **_w) {
 
   if (w->destroyed) return;
 
-  // One last synchronization
-  if (w->paint.pixmap)
-    xr_sync(ps, w->paint.pixmap, &w->fence);
-  free_fence(ps, &w->fence);
-
   // Set focus out
   win_set_focused(ps, w, false);
 
@@ -2545,16 +2529,6 @@ ev_name(session_t *ps, xcb_generic_event_t *ev) {
   if (ps->shape_exists && ev->response_type == ps->shape_event)
     return "ShapeNotify";
 
-#ifdef CONFIG_XSYNC
-  if (ps->xsync_exists) {
-    int o = ev->response_type - ps->xsync_event;
-    switch (o) {
-      CASESTRRET(XSyncCounterNotify);
-      CASESTRRET(XSyncAlarmNotify);
-    }
-  }
-#endif
-
   sprintf(buf, "Event %d", ev->response_type);
 
   return buf;
@@ -3402,6 +3376,7 @@ usage(int ret) {
     "--backend backend\n"
     "  Choose backend. Possible choices are xrender, glx, and\n"
     "  xr_glx_hybrid" WARNING ".\n"
+#undef WARNING
     "\n"
     "--glx-no-stencil\n"
     "  GLX backend: Avoid using stencil buffer. Might cause issues\n"
@@ -3426,20 +3401,6 @@ usage(int ret) {
     "  GLX backend: Use GL_EXT_gpu_shader4 for some optimization on blur\n"
     "  GLSL code. My tests on GTX 670 show no noticeable effect.\n"
     "\n"
-    "--xrender-sync\n"
-    "  Attempt to synchronize client applications' draw calls with XSync(),\n"
-    "  used on GLX backend to ensure up-to-date window content is painted.\n"
-#undef WARNING
-#ifndef CONFIG_XSYNC
-#define WARNING WARNING_DISABLED
-#else
-#define WARNING
-#endif
-    "\n"
-    "--xrender-sync-fence\n"
-    "  Additionally use X Sync fence to sync clients' draw calls. Needed\n"
-    "  on nvidia-drivers with GLX backend for some users." WARNING "\n"
-    "\n"
     "--glx-fshader-win shader\n"
     "  GLX backend: Use specified GLSL fragment shader for rendering window\n"
     "  contents.\n"
@@ -3457,6 +3418,7 @@ usage(int ret) {
     "--dbus\n"
     "  Enable remote control via D-Bus. See the D-BUS API section in the\n"
     "  man page for more details." WARNING "\n"
+#undef WARNING
     "\n"
     "--benchmark cycles\n"
     "  Benchmark mode. Repeatedly paint until reaching the specified cycles.\n"
@@ -3470,7 +3432,6 @@ usage(int ret) {
     ;
   FILE *f = (ret ? stderr: stdout);
   fputs(usage_text, f);
-#undef WARNING
 #undef WARNING_DISABLED
 
   exit(ret);
@@ -3996,8 +3957,12 @@ get_cfg(session_t *ps, int argc, char *const *argv, bool first_pass) {
         ps->o.write_pid_path = mstrcpy(optarg);
         break;
       P_CASEBOOL(311, vsync_use_glfinish);
-      P_CASEBOOL(312, xrender_sync);
-      P_CASEBOOL(313, xrender_sync_fence);
+      case 312:
+        printf_errf("(): --xrender-sync %s", deprecation_message);
+        break;
+      case 313:
+        printf_errf("(): --xrender-sync-fence %s", deprecation_message);
+        break;
       P_CASEBOOL(315, no_fading_destroyed_argb);
       P_CASEBOOL(316, force_win_blend);
       case 317:
@@ -4051,9 +4016,6 @@ get_cfg(session_t *ps, int argc, char *const *argv, bool first_pass) {
   if (ps->o.blur_background_frame)
     ps->o.blur_background = true;
 
-  if (ps->o.xrender_sync_fence)
-    ps->o.xrender_sync = true;
-
   // Other variables determined by options
 
   // Determine whether we need to track focus changes
@@ -5164,27 +5126,6 @@ session_init(session_t *ps_old, int argc, char **argv) {
     ps->shape_exists = true;
   }
 
-  if (ps->o.xrender_sync_fence) {
-#ifdef CONFIG_XSYNC
-    // Query X Sync
-    if (XSyncQueryExtension(ps->dpy, &ps->xsync_event, &ps->xsync_error)) {
-      // TODO: Fencing may require version >= 3.0?
-      int major_version_return = 0, minor_version_return = 0;
-      if (XSyncInitialize(ps->dpy, &major_version_return, &minor_version_return))
-        ps->xsync_exists = true;
-    }
-    if (!ps->xsync_exists) {
-      printf_errf("(): X Sync extension not found. No X Sync fence sync is "
-          "possible.");
-      exit(1);
-    }
-#else
-    printf_errf("(): X Sync support not compiled in. --xrender-sync-fence "
-        "can't work.");
-    exit(1);
-#endif
-  }
-
   // Query X RandR
   if ((ps->o.sw_opti && !ps->o.refresh_rate) || ps->o.xinerama_shadow_crop) {
     ext_info = xcb_get_extension_data(ps->c, &xcb_randr_id);
@@ -5498,7 +5439,6 @@ session_destroy(session_t *ps) {
     ps->tgt_picture = None;
   else
     free_picture(ps, &ps->tgt_picture);
-  free_fence(ps, &ps->tgt_buffer_fence);
 
   free_picture(ps, &ps->root_picture);
   free_paint(ps, &ps->tgt_buffer);
diff --git a/src/compton.h b/src/compton.h
index 040e495a..f89b543b 100644
--- a/src/compton.h
+++ b/src/compton.h
@@ -209,7 +209,6 @@ free_paint(session_t *ps, paint_t *ppaint) {
 static inline void
 free_wpaint(session_t *ps, win *w) {
   free_paint(ps, &w->paint);
-  free_fence(ps, &w->fence);
 }
 
 /**
diff --git a/src/config_libconfig.c b/src/config_libconfig.c
index 2a6f4e11..13d612a2 100644
--- a/src/config_libconfig.c
+++ b/src/config_libconfig.c
@@ -355,10 +355,6 @@ parse_config(session_t *ps, struct options_tmp *pcfgtmp) {
     exit(1);
   // --glx-use-gpushader4
   lcfg_lookup_bool(&cfg, "glx-use-gpushader4", &ps->o.glx_use_gpushader4);
-  // --xrender-sync
-  lcfg_lookup_bool(&cfg, "xrender-sync", &ps->o.xrender_sync);
-  // --xrender-sync-fence
-  lcfg_lookup_bool(&cfg, "xrender-sync-fence", &ps->o.xrender_sync_fence);
 
   if (lcfg_lookup_bool(&cfg, "clear-shadow", &bval))
     printf_errf("(): \"clear-shadow\" is removed as an option, and is always"
@@ -370,6 +366,10 @@ parse_config(session_t *ps, struct options_tmp *pcfgtmp) {
     printf_errf("(): \"glx-use-copysubbuffermesa\" %s", deprecation_message);
   if (lcfg_lookup_bool(&cfg, "glx-copy-from-front", &bval) && bval)
     printf_errf("(): \"glx-copy-from-front\" %s", deprecation_message);
+  if (lcfg_lookup_bool(&cfg, "xrender-sync", &bval) && bval)
+    printf_errf("(): \"xrender-sync\" %s", deprecation_message);
+  if (lcfg_lookup_bool(&cfg, "xrender-sync-fence", &bval) && bval)
+    printf_errf("(): \"xrender-sync-fence\" %s", deprecation_message);
 
   // Wintype settings
 
diff --git a/src/meson.build b/src/meson.build
index 79b55fbd..cd249399 100644
--- a/src/meson.build
+++ b/src/meson.build
@@ -1,6 +1,6 @@
 deps = [ cc.find_library('m'), cc.find_library('ev') ]
 
-cflags = [ '-DCONFIG_XSYNC' ]
+cflags = [ ]
 
 srcs = ['compton.c', 'win.c', 'c2.c', 'x.c', 'config.c']
 
diff --git a/src/opengl.c b/src/opengl.c
index 64abe5e7..fa8a9dd7 100644
--- a/src/opengl.c
+++ b/src/opengl.c
@@ -185,25 +185,6 @@ get_visualinfo_from_visual(session_t *ps, xcb_visualid_t visual) {
   return XGetVisualInfo(ps->dpy, VisualIDMask, &vreq, &nitems);
 }
 
-#ifdef CONFIG_GLX_SYNC
-void
-xr_glx_sync(session_t *ps, Drawable d, XSyncFence *pfence) {
-  if (*pfence) {
-    // GLsync sync = ps->psglx->glFenceSyncProc(GL_SYNC_GPU_COMMANDS_COMPLETE, 0);
-    GLsync sync = ps->psglx->glImportSyncEXT(GL_SYNC_X11_FENCE_EXT, *pfence, 0);
-    /* GLenum ret = ps->psglx->glClientWaitSyncProc(sync, GL_SYNC_FLUSH_COMMANDS_BIT,
-        1000);
-    assert(GL_CONDITION_SATISFIED == ret); */
-    XSyncTriggerFence(ps->dpy, *pfence);
-    XFlush(ps->dpy);
-    ps->psglx->glWaitSyncProc(sync, 0, GL_TIMEOUT_IGNORED);
-    // ps->psglx->glDeleteSyncProc(sync);
-    // XSyncResetFence(ps->dpy, *pfence);
-  }
-  glx_check_err(ps);
-}
-#endif
-
 #ifdef DEBUG_GLX_DEBUG_CONTEXT
 static inline GLXFBConfig
 get_fbconfig_from_visualinfo(session_t *ps, const XVisualInfo *visualinfo) {
diff --git a/src/win.h b/src/win.h
index e19af2cc..9b11b6b2 100644
--- a/src/win.h
+++ b/src/win.h
@@ -4,9 +4,6 @@
 #pragma once
 #include <stdbool.h>
 #include <X11/Xlib.h>
-#ifdef CONFIG_XSYNC
-#include <X11/extensions/sync.h>
-#endif
 #include <xcb/damage.h>
 
 // FIXME shouldn't need this
@@ -104,10 +101,6 @@ struct win {
   winmode_t mode;
   /// Whether the window has been damaged at least once.
   bool ever_damaged;
-#ifdef CONFIG_XSYNC
-  /// X Sync fence of drawable.
-  XSyncFence fence;
-#endif
   /// Whether the window was damaged after last paint.
   bool pixmap_damaged;
   /// Damage of the window.
diff --git a/src/x.c b/src/x.c
index 2d34500c..7e8aa3d7 100644
--- a/src/x.c
+++ b/src/x.c
@@ -317,17 +317,6 @@ x_print_error(unsigned long serial, uint8_t major, uint8_t minor, uint8_t error_
   }
 #endif
 
-#ifdef CONFIG_XSYNC
-  if (ps->xsync_exists) {
-    o = error_code - ps->xsync_error;
-    switch (o) {
-      CASESTRRET2(XSyncBadCounter);
-      CASESTRRET2(XSyncBadAlarm);
-      CASESTRRET2(XSyncBadFence);
-    }
-  }
-#endif
-
   switch (error_code) {
     CASESTRRET2(BadAccess);
     CASESTRRET2(BadAlloc);