it seems, that the <map> message freees pd, when it gets triggered on init, for example by loadbang.
just a meaningless example:

[x] <== set to "init"
[; pd-name_of_patch.pd map 0, map 1 (

...freezes pd'when restarting the patch. you could also use [loadbang] instead of the toggle.
can someone confirm this? i'm on linux mint 19.3.
thanks! ;-)