@HarborFront thanks for upping this thread alive
I like the two extensions and usually switch from one to the other.
Regarding the MV3 versions: uBO is faster, AG is way more mature with also more user configurable options.
Regarding the MV2 versions:
1. AdGuard (agree with @lnk it is the most user friendly option and the best choice for average and set and forget PC type of user)
Substantial advantages:
1. Is really set and forget (even adds language filters automatically)
2. Maintains its own filters, reducing the chance of website breakage
3. Offers the best filter AdBlock format compatibility (digests its own, uBO filter format and ABP format)
Minor advantages:
1. Has the most advanced element blocker/option to block ads manually using AG's 'block an ad' wizzard
2. Has the easiest to use logger (to add rules or create exceptions)
3. Includes Google Safe browsing option which is only a bonus for people using Edge Browsing - Chrome and Firefox use this option, so for these mainstream browser it is useless
4. Includes Stealth option (sets expiration date of cookies, which is only a bonus for people using Chrome - other mainstream browsers offer a option to delete all at browser close)
5. Is a company with paid subscription model and over 120 employees and often offers innovations first (because of their resources and manpower).
6. Has an option to use optimized filters (reducing overhead)
7. Has an option to allow functional ads. Although disliked by purists, this is a valued option for online shoppers (my wife values AG over uBO for this reason) to be informed about promotions on website they visit to buy something.
Disadvantages:
1. Allows to embed and import scriptlets in the filters (which could be a security risk)
2. Less focus on performance (good is enough, AG usually scores top 3 of fastest adblockers), so less attractive for geeks
3. Most of their development team resides in Russia, for some people this is a deal breaker, others don't really care (AG dared to post with #NoToWar tag)
2. uBlockOrigin (the best choice for PC-enthousiasts, hardcore adblockers, geeks and tweakers)
Substantial advantages
1. Purist attitude of developer towards security and privacy (resulting in more hard core privacy and security options)
2. Purist attitude of developer towards performance (resulting in the fastest, leanest adBlock extension avialable)
3. Processes more filter formats (imports ABP-format, Host format and its own dynamic format filters) providing the broadest scope of filters to play with
4. Is not as picky as other adblockers in the source format (imports filters without adblock version and other meta data) providing the best filter tweaking options of all adblockers
As an example: you can use AdGuard's base filter, or alternatively only add s subset of this filter (e.g. AdGuard's adserver's subfilter from Github), most other adblockers won't import this subfilter because this subfilter lacks a proper filter header (telling which adbloc version required, what the title is, what the expiration time, etc).
5. Offers a configurable pop-up menu (with loads of options)
6. Has dynamic filtering with an easy to tweak point and click option in popup menu
Minor advantages:
1. Has an extra block popup function in its own popup
2. Has an extra block popunder rule option in static filters
3. Has added From TO syntax for greater flexibility of static rules and easier conversion from dynamic to static rules
4. Offers stronger protection in Firefox (when on Windows Firefox lags behind Chromium based browsers in terms of security features).
5. Offers to add malware filter lists, but the effectiveness of those low update lists is minimal when using the browsers own browsing protection, a DNS with malware/phishing protection or an extension of a well known antivirus using cloud look-up.
Disadvantages:
1. Is a one-man band project, so the future depends on very limited manpower
2. uBO's own filters are not well maintained (because of the scarce manpower the focus is on correcting website breakage and not deleting old and obsolete rules)
3. Has the largest number of rules in the default filter set, so takes mini seconds longer for cold start and taking selfies (optimizing the ruleset). On slow hardware this might nihilate uBO's speed advantage over AdGuard. To uBO's credit in recent updates, a lot of badly maintained filterlist were removed (making it a tiny disadvantage)
