Change network connection timeout settings Firefox

1. Navigate to about:config.
2. Paste network.http.connection-timeout in the search bar.
3. The default value is 90 seconds. You can either change it to a longer duration by double-clicking on the value as seen in the image.
4. Or if you just want the extend the timeout duration of the retry attempts, repeat the process for network.http.connection-retry-timeout and change it instead.

As of April 2020, there is no way to disable the timeout setting in Firefox or Chrome.