[epiphany] Temporarily disable accelerated compositing mode

[Michael Catanzaro <mcatanzaro src gnome org>]

commit 23d6eb98313c0e3fc76cd2c3159f21586f11b1ff
Author: Michael Catanzaro <mcatanzaro igalia com>
Date:   Tue Dec 4 15:50:51 2018 -0600

    Temporarily disable accelerated compositing mode
    
    See #595

 embed/ephy-embed-prefs.c | 11 +++++++++++
 1 file changed, 11 insertions(+)
---
diff --git a/embed/ephy-embed-prefs.c b/embed/ephy-embed-prefs.c
index 9a61c5d2f..fda4f3f6a 100644
--- a/embed/ephy-embed-prefs.c
+++ b/embed/ephy-embed-prefs.c
@@ -435,6 +435,17 @@ ephy_embed_prefs_init (gpointer user_data)
                                                        "javascript-can-open-windows-automatically", TRUE,
                                                        NULL);
 
+  /* Accelerated compositing mode is pretty broken right now.
+   * Disable it entirely as a workaround for these bugs:
+   *
+   * https://bugs.webkit.org/show_bug.cgi?id=192230
+   * https://bugs.webkit.org/show_bug.cgi?id=192276
+   * https://gitlab.gnome.org/GNOME/gtk/issues/1401
+   *
+   * Of course this should be reverted when the bugs are fixed.
+   */
+  webkit_settings_set_hardware_acceleration_policy (webkit_settings, 
WEBKIT_HARDWARE_ACCELERATION_POLICY_NEVER);
+
   for (i = 0; i < G_N_ELEMENTS (webkit_pref_entries); i++) {
     GSettings *settings;
     char *key;