I think you could cut the URL length in half if you remap the JSON keys before compressing. Like turning
"total": 18,
"vatTableSummaryIsVisible": true,
"paymentMethod": "wire transfer",
"paymentMethodFieldIsVisible": true,
"paymentDue": "2025-08-27",
"stripePayOnlineUrl": "https://example.com",
"notes": "Reverse charge",
"notesFieldIsVisible": true,
"personAuthorizedToReceiveFieldIsVisible": false,
...
to this "1": 18,
"2": 1,
"3": "wire transfer",
"4": 0,
"5": "2025-08-27",
"6": "https://example.com",
"7": "Reverse charge",
"8": 1,
"9": 0,
...
Cut from ~1400 to ~700 chars in my testing, which is still a lot, so idk if you think it would be worth the extra code.