Firefox - XML Parsing Error: syntax error

[kkreft]

Additional information

1. This error occurs only on Firefox (was tested on version 60.0)
2. The error does not occur every time (there is no rule for that)
3. Even if the error shows up, the event is sent correctly
4. I see no impact on the response, it is always 200 with success msg.
5. Noticed on Amplitude-JavaScript 4.0.0 version

Error

XML Parsing Error: syntax error
Location: https://api.amplitude.com/
Line Number 1, Column 1:

Firefox Console Screenshot

Any suggestions are welcome.

[blazzy]

Hi @kkreft,

Could you show us what the response looks like too?

We haven't been able to reproduce the issue here. Do you have any extensions installed that might mess with or measure requests?

[kkreft]

@blazzy
The response has only success message. I checked even in Private Window (without any extensions) and the result is the same.

[aroget]

I am also noticing this as well, it only started a couple of days ago

[EthanML]

Yeah, we also see these constantly in our application when using Firefox. Same response as @kkreft . The only FF extensions I'm running are 1Password, the React devtools and Redux devtools.

[blazzy]

Sorry about that. Looks like a new event ingestion server rolled out without the appropriate response headers. This should be fixed soon.

[kkreft]

Great news @blazzy , thanks for taking care of this.

[bhuwanadhikari]

I am also getting this error but it appears only once and other things goes okay as usual. Does this affect after deployment of the app?

[alexandre1985]

I am getting this issue on my webpage. I do web development.
What is the root cause of this issue?

XML Parsing Error: syntax error
Location: https://www.brighterdan.com/en/?languageRedirection=done
Line Number 1, Column 1:

There does not seem to be an issue in my Line: 1, Column: 1 . Why such a obscure error message? I need better guiding error message.

[RaulCDev]

I am getting this issue on my webpage. I do web development. What is the root cause of this issue?

XML Parsing Error: syntax error
Location: https://www.brighterdan.com/en/?languageRedirection=done
Line Number 1, Column 1:

There does not seem to be an issue in my Line: 1, Column: 1 . Why such a obscure error message? I need better guiding error message.

Same here, any news?

[izaaz]

@RaulCDev - This SDK is deprecated. Can you please use the latest browser SDK from here?

https://github.com/amplitude/Amplitude-TypeScript

[blazzy]

I'm not sure recent posters are using Amplitude. Unfortunately, this issue just happens to be a high ranked result when someone pastes their various "XML Parsing Error" messages into Google.

I'd recommend locking this thread. @izaaz

Some browsers are finicky about Content-Type headers and will assume they should parse your http response as XML even if you are not serving XML. Amplitude made this mistake some 7 years ago where they deployed a new event server that did not explicitly set the content-type to "application/json" in its responses. It was fixed and is likely not an issue today. Either your server or some server you are communicating with isn't returning content that is matching the expected content type.