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Firefox does not send If-None-Match header for resources which had an etag in the previous response

  • 2 cavab
  • 2 have this problem
  • 13 views
  • Last reply by schlm3

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We have webservices which send json data to our webapp. The response headers have ETag-header and Chrome and IE11 correctly use that header (they send the etag in the if-none-match header of the next request). FF however ignores the etag and does not send it with the next request. I have already checked, that the cach in devtools is not deactivated. Thats how my response headers look like:

HTTP/1.1 200 Cache-Control: private X-Frame-Options: SAMEORIGIN X-Content-Type-Options: nosniff X-XSS-Protection: 1; mode=block Set-Cookie: JSESSIONID=0457E5621AE57A9F20350027834D7619; Path=/w3-dev; Secure; HttpOnly ETag: W/"bbb4975d-c81b" Vary: Accept-Encoding Content-Encoding: gzip Content-Type: application/json Content-Length: 1739 Date: Fri, 12 Apr 2019 19:52:46 GMT Server: -

And this is the requestheader from FF for the next request:

Host: bdna03:8443 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:66.0) Gecko/20100101 Firefox/66.0 Accept: application/json Accept-Language: de-CH,de;q=0.8,en-US;q=0.5,en;q=0.3 Accept-Encoding: gzip, deflate, br Referer: https://bdna03:8443/w3-dev/src/demo/index.html Connection: keep-alive Cookie: UID=XYdOZcb....

We have webservices which send json data to our webapp. The response headers have ETag-header and Chrome and IE11 correctly use that header (they send the etag in the if-none-match header of the next request). FF however ignores the etag and does not send it with the next request. I have already checked, that the cach in devtools is not deactivated. Thats how my response headers look like: HTTP/1.1 200 Cache-Control: private X-Frame-Options: SAMEORIGIN X-Content-Type-Options: nosniff X-XSS-Protection: 1; mode=block Set-Cookie: JSESSIONID=0457E5621AE57A9F20350027834D7619; Path=/w3-dev; Secure; HttpOnly ETag: W/"bbb4975d-c81b" Vary: Accept-Encoding Content-Encoding: gzip Content-Type: application/json Content-Length: 1739 Date: Fri, 12 Apr 2019 19:52:46 GMT Server: - And this is the requestheader from FF for the next request: Host: bdna03:8443 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:66.0) Gecko/20100101 Firefox/66.0 Accept: application/json Accept-Language: de-CH,de;q=0.8,en-US;q=0.5,en;q=0.3 Accept-Encoding: gzip, deflate, br Referer: https://bdna03:8443/w3-dev/src/demo/index.html Connection: keep-alive Cookie: UID=XYdOZcb....

All Replies (2)

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A thing which is strange is, that when I try to clean my local cache, it reports, that the cache has "0 Bytes". Seems that FF is not using a cache at all.

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I have now uninstalled FF and reinstalled it. Agreed to "start from scratch". This fixed the caching-problem.

But now, I have another problem. We use an internal CA-Certificate for our internal server TLS-Certificates. This was no problem with the former installation. I was easily able to import that CA into the Certificate store. But with the fresh installed FF 66.0.3, when ever I try to import the CA-Certificate, nothing happens. The Cert-Info Icon remains with an amber warning...