NanoAdblocker causes internet to "freeze" across entire browser

[judy]

I first reported this on NanoCore, Issue #294, and was told to make it here instead, as it only seems to affect Firefox for me.

Describe the issue (Required)

At random, the entire browser will act like the nothing on the Internet is responding. Like the router is frozen for a minute... but I've gone down a rabbit hole to figure out that it's NanoAdblocker.

Screenshots (Required)

Screenshot of console (Required, press F12 to open the console)

URLs where this issue occurs (Required if applicable)

All URLs.

Reproduction Steps (Optional if trivial)

This happens randomly, and I haven't figured out how to reproduce it on demand yet. Which makes this bug all the more irritating.

1. I will click on a link, or open a new tab or window to go to a new address. Nothing out of the ordinary, only regular internet browsing for work.
2. Firefox will start acting like the internet is taking an extremely long time to respond. Not just the link I clicked on, but any other link, opening new windows, etc.
3. Clicking on the NanoAdblocker extension
4. After roughly 60 seconds or so, NanoAdblocker starts responding, and all of the tabs I opened waiting for the internet to respond, start working at the same time. (I could time this if it would be useful.)

Anything else you believe to be useful (Optional)

For weeks now, I thought this was my internet connection, either my ISP or my router. Not like the connection has been broken, but like the packets are taking forever to respond, across all open Firefox tabs. The issue acts exactly like that would be the case, and I was preparing to plunk down a ton of money on replacing the router. So here's how I figured out that it's this extension:

Yesterday when it happened, I switched from my MacBook Pro to my PC, and realized that Firefox on it (with NanoAdblocker installed there too) was working just fine. That narrowed it down to the MacBook somehow.

So the second time it happened yesterday, I opened up Chrome, which has uBlock on it. That browser wasn't having issues either. I was also able to use curl and ping from the terminal without issues, so that narrowed it down to Firefox.

The third time it happened, I opened up a Private Browsing window. The issue was happening there. But the only extension I allow to run in Private Browsing was NanoAdblocker. (FWIW, I also have Nano Defender installed and running in Private Browsing, I haven't ruled it out yet). So I disabled it from Private Browsing and waited for the fourth time.

When the fourth time happened, I opened a new Private Browsing window in Firefox, and it was able to go to the same link I had been trying. Back in my regular Firefox window, I clicked on NanoAdblocker, and found that it was rendering only the outline of the dropdown, but none of the content inside it was loading.

Environment (Required)

• Operating System and Version: macOS Mojave 10.14.6
• Browser and Version: Firefox 70.0.1 (64-bit)
• Nano Adblocker Version: 1.0.0.131
• Nano Defender Version: 15.0.0.170

Your filter lists (Required)

Your custom filters (Required if you have any)

None here.

Your other extensions (Required if you have any)

• 1Password
• Bypass Paywalls
• Facebook Container
• Firefox Multi-Account Containers
• HTTPS Everywhere
• RescueTime for Firefox

Only NanoAdblocker and Nano Defender are enabled to run in Private Browsing.

[LiCybora]

I cannot resolve it if I do not know how to reproduce it.

Some tips for you if you really want to diagnose what's wrong:

• about:debugging#/runtime/this-firefox and click Inspect button for Nano Adblocker to view error logs.
• Try new default install on new fresh Firefox profile to see if you face it again, there are reports that Firefox may corrupt cache before.
• Close the tab or stop it if it wait too long, then open again to see if it is the same (or quickly disable NA to see if it will recover immediately for checking Firefox or NA goes wrong)
• Use shortcut to open logger (since you say clicking icon does not response) to see if it works and what are showing.
• Record the link, even you don't think it is related.

[SamirJouni]

Same issue. Disabled the add-on, restarted the browser, enabled it, and it works fine for now. One thing I can add is that it happened to me after the update from Firefox version 70.0.1 to Firefox version 71.0.

[spoolr]

Probably the same with me. I restarted the browser after a few weeks and it updated. The tab icon just spun and no HTML would display in the browser. I have dozens and dozens of tabs but nothing would show when I clicked on any of them. I created a new window and went to Google but got the same behaviour. Killed all the extensions and the ability to view the web was back. Started enabling extensions one by one and once NanoCoreFirefox is added Firefox can't display a tab anymore. I tried the above comment, disabled NanoCoreFirefox, restarted, and enabled NanoCoreFirefox but it didn't work. I had to remove it (not disable it), restart Firefox and then add NanoCoreFirefox back to restore operation. Everything is good again. Same version of NanoCoreFirefox is reported. Must be something about updating to Firefox 71.

[LiCybora]

I still cannot reproduce on Firefox 71 with default setup (neither 70 as OP reported).

However, I believe part of problem is from Firefox 71, since the upstream uBO mentioned that there are issue on uBO 1.23.0 with Firefox 71. Especially if you modify the about:config setting before.

I guess fixes require updating the core to uBO 1.24.2. It will spend some time however. The emergency workaround for now may be stay Firefox 70 or use default setting (probably related to First Party Isolation).