[Plugin: Contact Form 7] Widgets won't save

I love Contact Form 7, but for some reason when the plugin is enabled I can’t make changes to any of my sidebar widgets. The ‘spinner’ that comes up after I hit ‘Save’ just whirls away indefinitely, and changes to my widgets are never saved.

I have to disable Contact Form 7, update my widgets and then enable the plugin again. Any ideas?

https://www.ads-software.com/extend/plugins/contact-form-7/