Don't reload envelope thread (right pane) when searching

[st3iny]

Is your feature request related to a problem? Please describe.

When searching for an envelope the right pane is reloaded constantly each time the search "settles". This might be caused by the fact that the selected envelope is removed from the envelope list and added again right after depending on whether it is included in the search results or not.

This constant flickering is distracting.

Describe the solution you'd like

Don't reload the selected thread until the user manually selects a new envelope.

Describe alternatives you've considered

No response

Additional context

No response