Hi ,
According to the documentation : https://documentation.meraki.com/General_Administration/Organizations_and_Networks/Organization_Menu...
It is not specified but the changelog ( either via the API or the dashboard ) has a payload lenght of a maximum 4096 chars.
Eg :
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This means, if you have multiple L3 firewall rules and you modify them , the changelog will not report the complete change and only a part of it ( the first 4096 chars of that change ).
Not sure if it is the expected behavior , but I think it should be documented as a limitation if so.
Thanks ,