Please add "preview thumbnail update rate" control.

[wsy]

Hi,
My content in OBS does not change too much, so I would like to preview my thumbnail in a low frame rate such as 1fps, or manually.
I hope there can be something like this:

<span>Preview framerate:</span>
<select name="framerate">
    <option value="0">Manual refresh</option>
    <option value="1">1fps</option>
    <option value="2">2fps</option>
    <option value="5">5fps</option>
    <option value="10">10fps</option>
</select>