HTTP 4xx handling in WebView
Posted: Thu Mar 26, 2026 11:49 am
We have a plugin that runs a webview and then loads a web-app (sidebar) inside it. We noticed that when we have responses of 200, everything works fine but when we get 400 errors, our web-app doesn’t work properly. When we enable debugging, we can see the error attached. However, our web-app is unable to process the error. We tried reproducing the issue with a standalone JFX and Swing application but everything worked fine.
The 400 error has more information in the body and it seems this information is lost and hence the reason why our web-app doesn't seem to work as expected. The error has a json payload that has error detail, type, and title along with status.
Which leaves us with the question, why does this happen in Oxygen only and not in the browser or other applications that run the web-app?
We used Oxygen Editor version 25, 26, 27, and 28 for testing.
The 400 error has more information in the body and it seems this information is lost and hence the reason why our web-app doesn't seem to work as expected. The error has a json payload that has error detail, type, and title along with status.
Which leaves us with the question, why does this happen in Oxygen only and not in the browser or other applications that run the web-app?
We used Oxygen Editor version 25, 26, 27, and 28 for testing.
Code: Select all
ro.sync.net.protocol.http.HttpExceptionWithDetails: 400 Bad Request for: https://our-service.com/api/v1/check
at ro.sync.net.protocol.http.b.s.x(Unknown Source)
at ro.sync.net.protocol.http.b.s.c(Unknown Source)
at ro.sync.net.protocol.http.abstraction.n.r(Unknown Source)
at ro.sync.net.protocol.http.abstraction.n.e(Unknown Source)
at ro.sync.net.protocol.http.WebdavHttpURLConnection$_c.close(Unknown Source)
at com.sun.webkit.network.URLLoader.sendRequest(URLLoader.java:373)
at com.sun.webkit.network.URLLoader.doRun(URLLoader.java:163)
at com.sun.webkit.network.URLLoader.lambda$run$0(URLLoader.java:130)