I have the same problem as here: Facebook messenger checkbox plugin is hidden
I tried implementing the Facebook Checkbox plugin according to the Facebook documentation, but it will not appear on my virtual machine in my company.
The implementation of the SDK for Facebook works fine, I tried "Share" and "Like" -Button, which are displayed correctly.
I have a Facbook page that has open access and APP Messenger in DEV mode. Facebook's “Send-API” also works correctly: I can send a message to myself as an administrator from my web page on my development virtual machine.
The following steps are performed: use an arbitrary user_ref for each request, set my page to white list, use "https", visit my page FB-loggedIN and FB-loggedOut
But the result ends with Markup and Log-Infos, like this screen: See FF DeveloperTools Markup screenshot for current status
Accordingly, I visited the page indicated as origin , where the plugin should work (see the first link in my question) - but there the HTML code of the plugins is similar to mine.
So, is there a common problem on Facebook or is there even more needed to run this plugin? Maybe there is a problem with a self-signed certificate on my virtual machine?
At the moment, I do not want to notify the user or log in. All I want is to show a checkbox.
Maybe someone has an idea or the same experience :)
Additional information: the following fb:messenger_checkbox failed to resize in 45s message is displayed on the console fb:messenger_checkbox failed to resize in 45s