Updated description of "regex-based values as target domain for static extended filters" + more examples + link to related issue

Static-filter-syntax.md

@@ -2,7 +2,16 @@ uBlock Origin (uBO) supports most of the EasyList filter syntax. You can refer t
 
 While uBO does not support some specific cases, it further extends the EasyList filter syntax, which also may share with AG's extended syntax. [Here](./Syntax-quirks) are the most surprising cases documented.
 
-Starting with [1.46.1b15](https://github.com/gorhill/uBlock/commit/81498474d6d440b032681aa9952d593749b39efb), you can use regex-based values as target domain for static extended filters. Example of usage: `/img[a-z]{3,5}\.buzz/##+js(nowoif)`. Use sparingly, when no other solution is practical from a maintenance point of view -- keeping in mind that uBO has to iterate through all the regex-based values, unlike plain hostname or entity-based values which are mere lookups.
+Starting with [1.46.1b15](https://github.com/gorhill/uBlock/commit/81498474d6d440b032681aa9952d593749b39efb), you can use regex-based values as target domain for static extended filters. Examples of usage: 
+- `/img[a-z]{3,5}\.buzz/##+js(nowoif)`
+- solves: [Hiding rules are unable to specify to only block on the core domain and none of the subdomains (e.g. ~*.example.org doesn't work)](https://github.com/uBlockOrigin/uBlock-issues/issues/3291) :
+   - `/^example\.org$/##h1` - matches only `example.org` without subdomains
+   - `/^www\.example\.org$/##h1` - matches only `www.example.org` without subdomains and without `example.org`
+   - `/^(?:www\.)?example\.org$/##h1` - matches only `example.org` + `www.example.org` without subdomains
+
+- `/^example\.org$/,somesite.org##h1` - can also be combined with normal names
+
+Use sparingly, when no other solution is practical from a maintenance point of view -- keeping in mind that uBO has to iterate through all the regex-based values, unlike plain hostname or entity-based values which are mere lookups.
 
 - [Not supported](#not-supported)
 - [Pre-parsing directives](#pre-parsing-directives)