I have a simple visualforce page which loads a canvas app, the code looks like this:
<apex:canvasApp applicationName="AppName" namespacePrefix="namespace_prefix" height="1080px" width="100%"/>
It works fine in my developer account, and worked previously when I uploaded new "released" versions of the managed package, but as of today when I uploaded a new version of the managed package and upgraded to it, I got the following error when opening the Visualforce Tab which points at the above Visualforce page.
Force.com Canvas can not locate an installed canvas app with the namespace [namespace_prefix] and API name [namespace_prefix.AppName].
I then went and looked at the VisualForce page on the organization I had installed the package onto and I found the apex:CanvasApp code had changed!, on the org I upgraded the package on the Visualforce Page looked like:
<apex:canvasApp applicationName="namespace_prefix.AppName" namespacePrefix="namespace_prefix" height="1080px" width="100%"/>
If on that org I make a new Visualforce page that does not have the newly added "namespace_prefix." everything works fine and my canvas app loads up, but I cannot find a way to get my managed package to deploy the Visualforce page without adding the unwanted "namespace_prefix." to the applicationName, I also tried switching to using developerName instead of applicationName but the exact same thing happened.
It seems that this can be circumvented by uninstalling and reinstalling the package, but this is an unacceptable solution for our customers