inherit base type's plugin implementation
this fixes issue .
@@ -2092,6 +2092,10 @@ preparenext:
/* try to find loaded user type plugins */
plugin = lyplg_find(LYPLG_TYPE, tctx->tpdf->type.pmod->mod->name, tctx->tpdf->type.pmod->mod->revision,
tctx->tpdf->name);
+ if (!plugin && base) {
+ /* use the base type implementation if available */
+ plugin = base->plugin;
+ }
if (!plugin) {
/* use the internal built-in type implementation */
plugin = lyplg_find(LYPLG_TYPE, "", NULL, ly_data_type2str[basetype]);
