[BUG] Genesis widget mode parameter does not work with HTML elements

[pmario]

I wanted to create a simple / practical example for the genesis-widget, but found this.

To reproduce:

title: simplified-custom-widget-details
tags: $:/tags/Global

\widget $my.details(summary, open, mode)
\whitespace trim

<$genesis $type="details" 
  $names="open"
  $values={{{ [<open>match[true]] }}}
  $mode=<<mode>>
>
  <summary>
      <<summary>>
  </summary>
<$slot $name="ts-raw"/>
</$genesis>
\end

The following code should be rendered in block mode -> Bug - It's rendered inline

<$my.details summary="click me" mode="block" open >
! heading 1
</$my.details>

Widget tree looks as follows. -> The genesis widget gets the right parameter, but the ts-raw slot is not rendered in the right way.

If the slot-widget would have a $mode it could be set there.

@Jermolene, @saqimtiaz -- please have a closer look.