Add custom settings to form

[Rockerby]

Which Umbraco Forms version are you using? (Please write the exact version, example: 13.4.0)

13.4.2

Which Umbraco version are you using? (Please write the exact version, example: 13.5.2)

13.8.1

Issue summary

I'd like to be able to add additional settings to the form.

Specifics

My particular use case is that I want to add a "Submit form and start again" button to the final page of the form, but would like the button to be optional and added via user options.

I can workaround this by hardcoding something into the theme files and then showing/hiding with CSS (added to the form settings) but would be a much cleaner approach to be able to add my own settings to the form.

Steps to reproduce

There is no way to add custom settings to the form.

Expected result / actual result

To be able to add custom settings to the form and then be able to get the settings in code.

[umbracocommunity]

This issue has been mentioned on Umbraco community forum. There might be relevant details there:

https://forum.umbraco.com/t/umbraco-forms-custom-form-setting/4215/4