Select widgets by page

You can use one of these:

https://www.ads-software.com/extend/plugins/widget-logic/
https://www.ads-software.com/extend/plugins/dynamic-widgets/

Here’s an idea I’ve used before –

With a little JavaScript you could toggle visibility by using comment tags in the page content.

You could use a comment tag like this in your page content –
<!-- !widget-1 -->

Then use js to toggle the visibility of widget-1 –

p = $(this).html().split('!widget-1');
                if(p[1]){
                  $('.widget-1').hide();
                }

You can create any number of tags which would toggle specific widgets.

Perhaps one benefit to this method is that search engines would still index the widget content even if it’s not visible.

Just be sure you’re not reading the tags from page visitor-submitted comments. ??

I made a jQuery plugin to do something like this. Except you can use any HTML tag’s rel attribute to hold a list of object id’s or class names, like this –
Head:

<script type="text/javascript" src="https://code.jquery.com/jquery-latest.js"></script>
<script type="text/javascript" src="jquery.jlvisi.js"></script>

<script type="text/javascript">
	jQuery(document).ready(function () {
    $('#visibility').jlvisi();
});
</script>

Post or page content:
<span id="visibility" rel="!.widget-1,!.widget-2,*.widget-3"></span>
In this example, the span tag could be added to the post or page to control the visibility of the widgets listed in the rel attribute. The ! exclamation mark preceding a class name indicates the object will be hidden. The * asterisk preceding a class name indicates the object will be visible.

You can get the plugin at my website https://jasonlau.biz/home/jquery/jlvisi-a-jquery-plugin.