templates.Exists ignores module layouts (inside module (inside module (...)))

$ hugo version
Hugo Static Site Generator v0.80.0-792EF0F4/extended linux/amd64 BuildDate: 2020-12-31T13:46:18Z

I have a "weird" module structure:

my website (samui-samui.de)
loads a theme (garuda)
the theme loads a module for "blocks" (often used page components)
the blocks module loads a pwa module (that adds a service worker script).

In the blocks module there is a layout loaded from modules.

{{ $partialPath := "footer/service-worker" }}
{{ partial $partialPath . }}

This works. The footer/service-worker.html is in the pwa module, the code above is in the blocks module, hugo runs from the samui-samui.de website root "module" site, ... thingy...

Now I wanted to somehow add a fallback for if the pwa module is not installed:

{{ $partialPath := "footer/service-worker" }}
{{ if templates.Exists ( printf "partials/%s" $partialPath ) }}
  {{ partial $partialPath . }}
{{ else }}
  {{ warnf "service worker module not properly installed" }}
{{ end }}

This results in WARN 2021/02/07 22:01:23 service worker module not properly installed instead of loading the partial that exists and is properly mounted.

nothing like hugo mod vendor or hugo mod npm pack is done.
I have a local replace rule running

Garuda is public for testing, if you need access to samui-samui.de let me know and I'll add you to the repo.

gohugoio / hugo

templates.Exists ignores module layouts (inside module (inside module (...))) #8214