only available when compiled with +xim and +GUI_GTK Specifies the key that your Input Method in X-Windows uses for activation. When this is specified correctly, vim can fully control IM with 'imcmdline', 'iminsert' and 'imsearch'. You can't use this option to change the activation key, the option tells Vim what the key is. Format: [MODIFIER_FLAG-]KEY_STRING

    These characters can be used for MODIFIER_FLAG (case is ignored):
            S           Shift key
            L           Lock key
            C           Control key
            1           Mod1 key
            2           Mod2 key
            3           Mod3 key
            4           Mod4 key
            5           Mod5 key
    Combinations are allowed, for example "S-C-space" or "SC-space" are
    both shift+ctrl+space.
    See `<X11/keysymdef.h>` and XStringToKeysym for KEY_STRING.

    Example:

        :set imactivatekey=S-space

    "S-space" means shift+space.  This is the activation key for kinput2 +
    canna (Japanese), and ami (Korean).

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