iPadOS 16.4 external display only mirroring, no arrangement option with usb-c to VGA

There have been several observations from contributors concerning issues with external monitors - and Stage Manager - since updating to iPadOS 16.4.

In absence of documentation that might suggest an intended change to established functionality, issues such as yours are perhaps likely to be unintended - and may therefore be a bug. Here is one such thread:

iPad Extended Desktop not working - Apple Community

As such, you would be best advised to seek assistance directly from Apple Support. You can contact the Support Team using the Support link at top-right or bottom-left of this page. Alternatively and perhaps easier, you can initiate and manage your support cases using the excellent Apple Support App. If not already installed on your iPad, the App can be downloaded from the App Store:

https://apps.apple.com/app/apple-support/id1130498044

You might also consider submitting a Bug Report via Apple’s Product Feedback portal. For iPad and iPadOS:

Feedback - iPad - Apple

Just got off the phone with apple support for this same issue: extended display mode not working after upgrading to iPadOS 16.4.1. Spoiler, was able to resolve issue (with caveat that issue might come back, and if it does, I need to let them know).

I found that when plugging into my Sceptre brand dumb-TV with any adapter/dongle/hub the extended display support was not working and the iPadPro would only mirror its display to the TV. We tried plugging my iPadPro into my home office setup, with a Dell WD19DCS dock and Dell P2415Q display, the extended display support worked just fine.

It was suggested to try clearing out the brains on the TV, similar to how you might clear out the SMC on a mac. I then did the following

Turned off the TV

unplugged the TV from the iPadPro

unplugged the TV power cord from the wall outlet

pressed and held the TV power button for greater than 10 seconds

plugged the TV power cord back into the wall outled

Turned on the TV

plugged the TV back into the iPadPro

Then, like magic, extended display support was working just like it was supposed to on the TV. After this I retested it with all my usual hubs and found them all to be working as they had before. The hubs/docks tested were:

ElGato thunderbolt 3 professional dock

Caldigit SoHo dock

Twelve South StayGo hub

Cable Creations usb c hub

Apple Digital AV adapter

Now mind you that this was a very surprising result, as the same docks and TV were still working just fine with a 2017 MacBook Pro, so it didn’t seem like the issue should have been related to the TV. Best we could figure is they just weren’t communicating correctly and resetting the TV made the iPadPro try its handshake a little differently (figuratively speaking). Maybe something was cached weirdly that made it act up after the iPadOS update.

So try resetting the memory on whatever display you are attempting to plug in to and that might just resolve your issue!