[Bug]: Connection to Environments with mcas.ms URL not possible

[ganfer]

What happened?

First of all, thanks for sharing PPTB on ColorCloud 2026. Really enjoyed the session and tried it out right now.

I am experiencing an issue when trying to create a connection to certain Power Platform environments using Power Platform Toolbox.
Connections work as expected for environments with standard URLs like:
https://orgname.crm4.dynamics.com

However, for customers whose environment URLs are wrapped via Microsoft Defender for Cloud Apps and therefore look like this:
https://orgname.crm4.dynamics.com.mcas.ms
for me, it is not possible to establish a connection in Power Platform Toolbox.

That's very sad, because a lot of my customers use MS Defender for Cloud Apps and I am not able to use the PPTB as I want to :)

Best Regards
Ferdinand

What version of the PPTB are you using?

28.3.3

Relevant log output

Invalid Input

Please provide a valid Dynamics 365/Dataverse URL
(e.g., https://orgname.crm.dynamics.com or
https://orgname.crm.microsoftdynamics.us).

[OliverFlint]

Need to update the regex for url validation.

e.g. /^[a-zA-Z0-9]([a-zA-Z0-9-]*[a-zA-Z0-9])?\.crm\d*\.(dynamics\.com|microsoftdynamics\.us|appsplatform\.us)(\.mcas\.ms)?$/i

desktop-app/src/renderer/modules/connectionManagement.ts

Line 1476 in 2c6727c

const DATAVERSE_HOST_PATTERN = /^[a-zA-Z0-9]([a-zA-Z0-9-]*[a-zA-Z0-9])?\.crm\d*\.(dynamics\.com|microsoftdynamics\.us|appsplatform\.us)$/i;