Not able to support two external display with Dell WD19 on MacBook Pro M3 Pro

I'm afraid that information is not completely right.

Dell WD19 supports Thunderbird and it's specified under "USB 3.1 Gen1/Gen2 Type-C with DisplayPort 1.4".

It's even highlighted in https://www.dell.com/support/manuals/en-uk/dell-wd19-130w-dock/wd19_userguide/important-information?guid=guid-91250737-e143-411a-b9d5-aafc1bb7b802&lang=en-us.

Macbook pro with M3 chip has probably some compatibility issues with Thunderbird standard or vicerversa, which I'm trying to figure out myself too. I need to update the dock to the latest firmware issued in January before I try again.

But maybe this post on Dell website can help to understand the compatibility story https://www.dell.com/support/kbdoc/en-uk/000124312/dell-thunderbolt-dock-wd19tb-and-apple-usb-c-hosts but that's WD19TB not WD19.

My understanding is that Macs only support driving two monitors off a single port when

• The Mac supports multiple external monitors
• The device plugged directly into the Mac is a Thunderbolt device of some sort, like a Thunderbolt dock or hub

A MBP with a M3 Pro chip can support two external monitors, and has Thunderbolt ports. On the other hand, the Dell WD19 appears to be a plain USB-C dock, not a Thunderbolt one.

https://www.dell.com/support/manuals/en-us/dell-wd19-130w-dock/wd19_userguide/docking-specifications?guid=guid-cd615eef-5015-4931-bf9b-e19f9cf50c4d&lang=en-us

You might want to look into Thunderbolt docks and hubs, like those offered by Other World Computing (MacSales) and SonnetTech

https://eshop.macsales.com/shop/thunderbolt/thunderbolt-docks

https://www.sonnettech.com/product/thunderbolt/docks-and-hubs.html

daN4cat wrote:

Dell WD19 supports Thunderbird

Thunderbird ?!?

It was meant to read Thunderbolt, I cannot edit the answer now.