Save of Read Only widget fails in hard to debug way when Geocoder Field is enabled

Problem/Motivation

Trying to set a text field to read only while Geocoder is installed, but even though i am setting the Format to plain text and the Geocoder options correctly go away, pressing update on the field widget has no effect and saving the "Manage form display" form is prevented by this error:

"The selected Geocode operation needs at least one provider."

Cross-posting from 💬 Read-only Field Widget not meant to use geocoder, cannot save widget due to geocoder_field error Needs review in Geocoder project because we think this might be something better fixed in Readonly Field Widget, or at least Geocoder could get guidance on the best way to fix.

Steps to reproduce

1. Install Geocoder Field (geocoder_field) and Read Only Field Widget modules
2. Edit a text field to use it, changing Format to "Plain text"
3. Try to save the form display

Proposed resolution

Can Read Only avoid triggering the widget settings form processing of widgets that are not currently selected by it?

Remaining tasks

User interface changes

API changes

Data model changes