--- /dev/null
+From: Simon McVittie <smcv@debian.org>
+Date: Sat, 17 Sep 2022 18:53:00 +0100
+Subject: gdkevents: Don't ignore modifiers that are not currently active
+
+The X11 backend can mark modifiers like Shift as consumed even if they
+aren't actually active, which seems to be something to do with making
+shortcuts like `<Control><Shift>plus` and `<Control>plus` work as
+intended regardless of whether the plus symbol is obtained by pressing
+Shift and a key (like `+/=` on American, British or French keyboards)
+or not (like `*/+` on German keyboards).
+
+However, this can go badly wrong when the modifier is *not* pressed.
+For example, terminals normally have separate bindings for `<Control>c`
+(send SIGINT) and `<Control><Shift>c` (copy). If we disregard the
+consumed modifiers completely, when the X11 backend marks Shift as
+consumed, pressing Ctrl+c would send SIGINT *and* copy to the clipboard,
+which is not what was intended.
+
+By masking out the members of `consumed` that are not in `state`, we
+get the same interpretation for X11 and Wayland, and ensure that
+keyboard shortcuts that explicitly mention Shift can only be triggered
+while holding Shift. It continues to be possible to trigger keyboard
+shortcuts that do not explicitly mention Shift (such as `<Control>plus`)
+while holding Shift, if the backend reports Shift as having been
+consumed in order to generate the plus keysym.
+
+Bug: https://gitlab.gnome.org/GNOME/gtk/-/issues/5095
+Bug-Debian: https://bugs.debian.org/1016927
+Signed-off-by: Simon McVittie <smcv@debian.org>
+Forwarded: https://gitlab.gnome.org/GNOME/gtk/-/merge_requests/5037
+---
+ gdk/gdkevents.c | 22 +++++++++++++++++++---
+ 1 file changed, 19 insertions(+), 3 deletions(-)
+
+diff --git a/gdk/gdkevents.c b/gdk/gdkevents.c
+index 4b61715..0daf475 100644
+--- a/gdk/gdkevents.c
++++ b/gdk/gdkevents.c
+@@ -1773,7 +1773,7 @@ gdk_key_event_matches (GdkEvent *event,
+ guint ev_keyval;
+ int layout;
+ int level;
+- GdkModifierType consumed_modifiers;
++ GdkModifierType ignored_modifiers;
+ GdkModifierType shift_group_mask;
+ gboolean group_mod_is_accel_mod = FALSE;
+ const GdkModifierType mask = GDK_CONTROL_MASK |
+@@ -1792,7 +1792,23 @@ gdk_key_event_matches (GdkEvent *event,
+ ev_keyval = self->translated[1].keyval;
+ layout = self->translated[1].layout;
+ level = self->translated[1].level;
+- consumed_modifiers = self->translated[1].consumed;
++
++ /*
++ * If a modifier is currently active (e.g. Shift is pressed) and was marked
++ * as consumed, we ignore it for the purposes of matching shortcuts.
++ * For example, when Ctrl+Shift+[plus/equals key] is translated into
++ * Ctrl+plus on a keyboard where Shift+equals is the plus sign, we want
++ * shortcuts for either <Control><Shift>plus or <Control>plus to match.
++ * (See https://bugzilla.gnome.org/show_bug.cgi?id=100439)
++ *
++ * If a modifier is *not* currently active, the X11 backend can sometimes
++ * mark it as consumed where the Wayland and Windows backends do not.
++ * In this case, we still want to pay attention to its state.
++ * For example, when Ctrl+x is translated into Ctrl+x, we only want to
++ * trigger shortcuts for <Control>x, not for <Control><Shift>x.
++ * (See https://gitlab.gnome.org/GNOME/gtk/-/issues/5095)
++ */
++ ignored_modifiers = (self->translated[1].consumed & state);
+
+ /* if the group-toggling modifier is part of the default accel mod
+ * mask, and it is active, disable it for matching
+@@ -1804,7 +1820,7 @@ gdk_key_event_matches (GdkEvent *event,
+ if (mask & shift_group_mask)
+ group_mod_is_accel_mod = TRUE;
+
+- if ((modifiers & ~consumed_modifiers & mask) == (state & ~consumed_modifiers & mask))
++ if ((modifiers & ~ignored_modifiers & mask) == (state & ~ignored_modifiers & mask))
+ {
+ /* modifier match */
+ GdkKeymapKey *keys;
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