Ticket #43091: Portfile.diff

Portfile

@@ -94 +94 @@
 
     if {${python.version} > 26} {
         variant gtk3 description "Enable GTK3Agg backend" {
-            depends_lib-append  port:py${python.version}-gobject3
+            depends_lib-append  port:py${python.version}-gobject3 port:gtk3
             post-patch {
                 reinplace "s|^gtk3agg=False|gtk3agg=True|" ${worksrcpath}/setup.cfg
             }