POST limitations between Add & Edit?

I have some custom code pages for adding records. The forms generated by the code pages include signature capture. The code takes the canvas and converts the data to Base64. The image is displayed on the form using the Base64 and also is added to a URL field when the record is saved. I use a formula URL field to add the "data:image/png;base64," to the beginning of the DataURL string and then use a formula rich text field to display the image in the native Quickbase form.

This works without any issues.

I am working on a button that opens the signature to allow editing it. When I save the edited signature I get an HTTP Error 400: The size of the request headers is too long. When I look at the URL it has the entire DataURL along with the encoding for special characters like '+', so the payload is constructed correctly.

So the DataURL POSTs with no issue when I add, but it is too long when I edit. Is there a different limitation for edit versus add? Otherwise I see no reason why I get this error.

Here is an example of a captured signature displayed in the native Quickbase form:

Here is what it looks like in the custom form:



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Adam Keever
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