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Fetching extension fails under MITM proxy even if certificate is added

  • 3 replies
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  • 1 view
  • Last reply by GamePlayer

GamePlayer
GamePlayer
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Good afternoon,

I've got a problem with add-ons while using Squid MITM Proxy with a custom certificate for Firefox/LibreWolf.

While I'm trying to update / install an extension / theme, it fails with:

``` 1686147276233 addons.xpi WARN Download of https://addons.mozilla.org/firefox/downloads/file/4104397/witchdoctor-2.0.xpi failed: [Exception... "Certificate issuer is not built-in." nsresult: "0x80004004 (NS_ERROR_ABORT)" location: "JS frame :: resource://gre/modules/CertUtils.sys.mjs :: checkCert :: line 177" data: no] Stack trace: checkCert()@resource://gre/modules/CertUtils.sys.mjs:177 onStopRequest()@resource://gre/modules/addons/XPIInstall.jsm:2514 ```

How can I install an add-on while using the MITM proxy?

Good afternoon, I've got a problem with add-ons while using Squid MITM Proxy with a custom certificate for Firefox/LibreWolf. While I'm trying to update / install an extension / theme, it fails with: ``` 1686147276233 addons.xpi WARN Download of https://addons.mozilla.org/firefox/downloads/file/4104397/witchdoctor-2.0.xpi failed: [Exception... "Certificate issuer is not built-in." nsresult: "0x80004004 (NS_ERROR_ABORT)" location: "JS frame :: resource://gre/modules/CertUtils.sys.mjs :: checkCert :: line 177" data: no] Stack trace: checkCert()@resource://gre/modules/CertUtils.sys.mjs:177 onStopRequest()@resource://gre/modules/addons/XPIInstall.jsm:2514 ``` How can I install an add-on while using the MITM proxy?

All Replies (3)

Dropa
Dropa
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If the certificate is failing you should contact their customer service support about this issues since that extension is from them. Addon install issues should contact their Developer for support on their Addon.

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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You can try to download and save the extension's XPI file and install the extension via the about:addons page via the cogwheel menu.

GamePlayer
GamePlayer Question owner
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At the moment there's no way to install extension through MITM?