Mesh plugin: Doesn't render with \App\template

I am using the Mesh plugin (which is very nice btw) to have multiple editable fields in backend.

The theme is also a onepager theme, modified code from
the twentyseventeen code is used, adjusted to a sage based theme

However, echo \App\template('single-panels'); renders the page without Mesh markup.
It works with a single sage9 based (blade) paged.
Apparently \App\template(...) doesn’t seem to invoke the hooks/actions the Mesh plugin expects.
Is there an even higher-level method in sage that can be used for rendering a page?

How can I use \App\template that also the loop_end and
other loop actions are used, like rendering the whole page.

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