I was able to solve this issue last night by using the OpenCV plugin. Using their  Utils.textureToTexture2D F(x) I was able to get the background plane background.

What issues are you encountering?



If you can't get the texture your problem might be unrelated to the one described in this thread



The background plane renderer is instantiated as a child of the AR camera the moment Vuforia is started and you see the camera feed, you can get it by doing 

ARCamera.GetComponentInChildren<BackgroundPlaneBehaviour>().GetComponent<MeshRenderer>().material.mainTexture;



you could also try using VuforiaRenderer.Instance.VideoBackgroundTexture





you should share with us your unity version, it is working fine for me on 2018.2.19

@Rilissimo Your instructions for downgrading worked perfectly. Unfortunately, I was still unable to get the background plane texture... So I will work on finding other solutions. 

Thanks for the info. I would never blame you if this wouldn't work. Ill give it a try and let you know! Thanks!

If I share them I do not take any resposibility for any issues,



How I did it was to take the files from an old vuforia installation in another unity editor installation and copying them to the desired unity folder(i didn't have the original installer)



https://drive.google.com/file/d/1TDA6oYIjxsIpCFZZ-cwyNyrVRmyzD5LV/view?usp=sharing



If anything goes wrong I suggest you uninstall everything and resintall from scratch and wait for a fix on vuforia's part.

that folder needs to go in Unity/Editor/Data/PlaybackEngines



once unpacked you need to edit ivy.xml to your desired unity version, you'll also need to delete all vuforia related assets from your project (make a backup always) and reimport the package found in VuforiaSupport/VuforiaResources (it should be "vuforia-unity.unitypackage")



Do this whole procedure at your own risk and only if you absolutely need stuff working again quickly

@Rilissimo

Is it possible to share those files with the people who don't have that version of vuforia?

Thank you, in the meanwhile I managed to copy the old vuforiasupport folder from my previous unity installation into the newer one (7.5.26) and everything works fine again

If you need anything else let me know

Hello,

Thanks for the feedback. I've opened a ticket for additional investigation into the issue.

Thanks,

Vuforia Engine Support