Removed GTK2 compatibility shims from headers (fe-gtk.h, gtkutil.h), leaving direct GTK3-facing declarations/includes only (and platform-specific guards unrelated to GTK2 kept as-is).
Cleaned GTK2-specific comments/wording now that behavior is GTK3-native (menu accelerator note and emoji/userlist comment blocks).
Switched GtkXText and CustomList implementations to G_DEFINE_TYPE/G_DEFINE_TYPE_WITH_CODE and preserved parent chaining behavior
Added GTK3/GTK2 conditional type declarations for GtkXText while restoring the legacy macro block for GTK2 builds.
Restored GTK2-friendly typedefs/macros and parent field naming for CustomList alongside GTK3 G_DECLARE_DERIVABLE_TYPE usage.
Restored GTK2-friendly typedefs/macros and parent field naming for SexySpellEntry while keeping GTK3 declarations intact.
Restored legacy RemoteObject typedefs and GType macros in the D-Bus plugin to keep GTK2 builds from seeing incomplete types or missing fields/macros.