How would you find out whether or not you've hit your custom activities limit? Is there a way to see that in MKTO or do you have to contact your MKTO rep?
Yes, but not trivially.
The default limit is 10. You can see how many you have currently configured under Admin, Database Management, Custom Activities. The UI reveals the configured limit when you attempt to exceed it.
If you do, you'll receive the error message with a red banner: "Sorry! The activity could not be created. There are already XX custom activities in your subscription." Where XX is the currently configured limit for your instance.
Each Custom Activity has one primary attribute and up to 20 secondary attributes offering significant flexibility in the way they can be utilized. An improved schema can often reduce the number of custom activities required.
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