On Tuesday, Facebook announced it will begin showing ads in desktop browsers “for people who currently use ad blocking software.” Adblock Plus, the most popular ad blocking tool with over 500 million downloads, responded the same day by calling the move “a dark path against user choice.” Today, just two days later, Adblock Plus is offering a workaround that users can implement themselves now, and which will automatically take effect for all users in “a couple of days.”

The workaround consists of a new filter added to EasyList, the most popular Adblock Plus filter list that is officially recommended by the program. Here is the code you need to add if you want to do so manually:

facebook.com##DIV[id^=”substream_”] ._5jmm[data-dedupekey][data-cursor][data-xt][data-xt-vimpr=”1″][data-ftr=”1″][data-fte=”1″]

The instructions for updating your filter list vary by browser.

In Firefox:

Select Firefox >> Add-ons (for Mac OS X / Linux, select “Tools” from the menubar >> “Add-Ons”), this will open your Firefox Add-ons Manager. Click on “Extensions”, find Adblock Plus there, go to “Options” and then click on “Filter preferences…”. Press this shortcut key to update all filter subscriptions at once: Ctrl+Shift+T or right-click a filter subscription and choose “Update filters”.

In Chrome:

Click the Chrome menu button, then go to “Tools” and choose “Extensions”. Find Adblock Plus there and click on “Options” under its description. Click the “Update now” button.

In Opera:

Click the “Menu” button (for Mac OS X / Linux, “Tools”), select “Extensions” >> “Manage Extensions”. Find Adblock Plus there and click its small tool icon on the right side and choose “Preferences”. Click the “Update now” button.

If that’s too much effort, just wait until the filter list is updated automatically.

This story is far from over. As Adblock Plus notes, Facebook could “re-circumvent” this workaround for ad blockers on its site at any time. As the company rightly describes, this is a cat-and-mouse game: Every time Facebook changes something, the ad-blocking community will respond in turn.

We’ve contacted Facebook and will update this story if the company has anything to say.

Update at 9:48 a.m. Pacific: Facebook isn’t going to give up that easily.

“We’re disappointed that ad blocking companies are punishing people on Facebook as these new attempts don’t just block ads but also posts from friends and Pages,” a Facebook spokesperson told VentureBeat. “This isn’t a good experience for people and we plan to address the issue. Ad blockers are a blunt instrument, which is why we’ve instead focused on building tools like ad preferences to put control in people’s hands.”

Update at 11:18 a.m. Pacific: Adblock Plus says that “From what we can see the fix is working perfectly well.”

“On a more general level, ad blocking gives people complete control of their internet experience; they can block just the annoying ads, all the ads, tracking, malware and a lot more,” Adblock Plus head of operations Ben Williams told VentureBeat. “Unfortunately, their claims of offering user control ring a bit hollow when they force those who have opted out of traditional ads to view ads — regardless of whether the users can choose which ads to see.”

Update on August 12: At some point yesterday, Facebook rolled out code that again circumvented Adblock Plus’ workaround. Adblock Plus found another workaround. Today, it happened again. Facebook circumvented, and Adblock Plus responded with yet another workaround. All users have to do is update their filters using the above instructions above.

In the meantime, Adblock Plus continues to blast Facebook:

Anger or blame toward ad blockers is misdirected; we merely enforce “the will of the people” (via the open-sourced filter lists). Should Facebook circumvent again, I’m sure another solution will arise from that open source community. And so on … What is the solution? We invite publishers and websites to work with Adblock Plus and our whitelisting process, rather than circumventing consumers’ expressed concerns. We clearly feel like giving users control of their internet experience is better than taking it away, and it’s disheartening that a company like Facebook would abuse everyone’s experience of their site by forcing that experience into a one-size-fits-all, see-the-ads-or-else tube. The internet just doesn’t work that way. At least it shouldn’t.

The game of cat and mouse continues.