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Firefox can’t establish a connection to the server at ws://127.0.0.1 (plugin or setting is causing this, how to discover exact cause?)

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Hello, Firefox 91.0.2 shows in dev. console: Firefox can’t establish a connection to the server at ws://127.0.0.1

The Private browsing window has the issue too, but i am unsure if it really disable all extensions.

When i use different Firefox profile, then the localhost site i am trying to load is loaded without that error. So how to discover please which FIrefox profile setting is preventing the loading please?

Hello, Firefox 91.0.2 shows in dev. console: Firefox can’t establish a connection to the server at ws://127.0.0.1 The Private browsing window has the issue too, but i am unsure if it really disable all extensions. When i use different Firefox profile, then the localhost site i am trying to load is loaded without that error. So how to discover please which FIrefox profile setting is preventing the loading please?

Modified by #367259

Chosen solution

Tried: FF hamburger menu, Help, Troubleshoot mode... it started working in this no-extensions mode, and after restart to normal mode it is still working. So the workaround was to restart Firefox? :-/

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Chosen Solution

Tried: FF hamburger menu, Help, Troubleshoot mode... it started working in this no-extensions mode, and after restart to normal mode it is still working. So the workaround was to restart Firefox? :-/