OK… I appreciate the detailed posts and what you are trying to do, and the link to a potential solution. However, it still involves modifying the plugin to add/enqueue some javascript as shown in that link, and then modifying the PHP part of the plugin to see if that parameter has been added to the form, and add it to all the generated links. Not something that would necessarily be useful to anyone else, and still belongs in the “feature requests” category with all the other requests that people ask for (plus all the others that people email me about without adding them to the feature requests section).
However, there may be a slight work-around that may do what you want. In that link to your own signup page you gave me, seems like you have a simple list of dates/sheets that are clickable links that then open a sheet with the list of tasks.
Here is what you can do, and that I have tested with my own plugin:
- Create a separate page/post for each sheet and use one shortcode with the id argument that goes with the sheet you want to show on that page.
- In my plugin settings where there is a select box to set the main volunteer page, leave that set to “none”
- Create a page like your main volunteer page where you have links to each of those pages you just set up.
If you do the above, and they go to one of those pages with the single id shortcode, and then click on something to signup for, after they signup and click to go back, they will go back to that specific signup sheet page they started (because you haven’t set up a default page in the options to return to).
Optionally, you can also purchase my Groups extension:
https://stephensherrardplugins.com/plugins/pta-volunteer-sign-up-sheet-groups/
and then you can arrange sign-up sheets into groups and use a shortcode to display just that group’s list of sheets. When the groups shortcode argument exists, the return links will be reworded to direct them back to the page with the shortcode for that group.
Perhaps one of these methods might work for you without any additional custom programming.