Readme tweaks

README.md

@@ -651,7 +651,7 @@ Notice that nearly every feature below has at least subtle differences from Java
     <td align="middle">☑️</td>
     <td align="middle">☑️</td>
     <td>
-      ● Common uses supported<br>
+      ● Common uses supported<sup>[4]</sup><br>
     </td>
   </tr>
   <tr valign="top">
@@ -800,7 +800,7 @@ Notice that nearly every feature below has at least subtle differences from Java
     <td align="middle">☑️</td>
     <td align="middle">☑️</td>
     <td>
-      ✔ Error if group to the right<sup>[4]</sup><br>
+      ✔ Error if group to the right<sup>[5]</sup><br>
       ✔ Duplicate names (and subroutines) to the right not included in multiplex<br>
       ✔ Fail to match (or don't include in multiplex) ancestor groups and groups in preceding alternation paths<br>
       ❌ Some rare cases are indeterminable at compile time and use the JS behavior of matching an empty string<br>
@@ -854,7 +854,7 @@ Notice that nearly every feature below has at least subtle differences from Java
     <td align="middle">☑️</td>
     <td align="middle">☑️</td>
     <td>
-      ● Has depth limit<sup>[5]</sup><br>
+      ● Has depth limit<sup>[6]</sup><br>
     </td>
   </tr>
   <tr valign="top">
@@ -867,7 +867,7 @@ Notice that nearly every feature below has at least subtle differences from Java
     <td align="middle">☑️</td>
     <td align="middle">☑️</td>
     <td>
-      ● Has depth limit<sup>[5]</sup><br>
+      ● Has depth limit<sup>[6]</sup><br>
     </td>
   </tr>
 
@@ -931,15 +931,16 @@ Notice that nearly every feature below has at least subtle differences from Java
   </tr>
 </table>
 
-The table above doesn't include all aspects that Oniguruma-To-ES emulates (including error handling, most aspects that work the same as in JavaScript, and many aspects of non-JavaScript features that work the same in the other regex flavors that support them).
+The table above doesn't include all aspects that Oniguruma-To-ES emulates (including error handling, most aspects that work the same as in JavaScript, and many aspects of non-JavaScript features that work the same in the other regex flavors that support them). Where applicable, Oniguruma-To-ES follows the latest version of Oniguruma (currently 6.9.9).
 
 ### Footnotes
 
 1. Unicode blocks (which in Oniguruma are used with an `In…` prefix) are easily emulatable but their character data would significantly increase library weight. They're also a flawed and arguably unuseful feature, given the ability to use Unicode scripts and other properties.
 2. With target `ES2018`, the specific POSIX classes `[:graph:]` and `[:print:]` use ASCII-based versions rather than the Unicode versions available for target `ES2024` and later, and they result in an error if using strict `accuracy`.
 3. Target `ES2018` doesn't support nested *negated* character classes.
-4. It's not an error for *numbered* backreferences to come before their referenced group in Oniguruma, but an error is the best path for Oniguruma-To-ES because (1) most placements are mistakes and can never match (based on the Oniguruma behavior for backreferences to nonparticipating groups), (2) erroring matches the behavior of named backreferences, and (3) the edge cases where they're matchable rely on rules for backreference resetting within quantified groups that are different in JavaScript and aren't emulatable. Note that it's not a backreference in the first place if using `\10` or higher and not as many capturing groups are defined to the left (it's an octal or identity escape).
-5. The recursion depth limit is specified by option `maxRecursionDepth`. Overlapping recursions and the use of backreferences when the recursed subpattern contains captures aren't yet supported. Patterns that would error in Oniguruma due to triggering infinite recursion might find a match in Oniguruma-To-ES since recursion is bounded (future versions will detect this and error at transpilation time).
+4. Examples of supported uses of `\G` include `\G…`, `\G…|\G…`, `(?<=…)\G…`, `(^|\G)…`, `(?!\G)…`, and many other variations.
+5. It's not an error for *numbered* backreferences to come before their referenced group in Oniguruma, but an error is the best path for Oniguruma-To-ES because (1) most placements are mistakes and can never match (based on the Oniguruma behavior for backreferences to nonparticipating groups), (2) erroring matches the behavior of named backreferences, and (3) the edge cases where they're matchable rely on rules for backreference resetting within quantified groups that are different in JavaScript and aren't emulatable. Note that it's not a backreference in the first place if using `\10` or higher and not as many capturing groups are defined to the left (it's an octal or identity escape).
+6. The recursion depth limit is specified by option `maxRecursionDepth`. Overlapping recursions and the use of backreferences when the recursed subpattern contains captures aren't yet supported. Patterns that would error in Oniguruma due to triggering infinite recursion might find a match in Oniguruma-To-ES since recursion is bounded (future versions will detect this and error at transpilation time).
 
 ## ❌ Unsupported features
 
@@ -962,16 +963,17 @@ The following don't yet have any support, and throw errors. They're all infreque
 
 Oniguruma-To-ES fully supports mixed case-sensitivity (and handles the Unicode edge cases) regardless of JavaScript [target](#target). It also restricts Unicode properties to those supported by Oniguruma and the target JavaScript version.
 
-Oniguruma-To-ES focuses on being lightweight to make it better for use in browsers. This is partly achieved by not including heavyweight Unicode character data, which imposes a couple of minor/rare restrictions:
+Oniguruma-To-ES focuses on being lightweight to make it better for use in browsers. This is partly achieved by not including heavyweight Unicode character data, which imposes some minor/rare restrictions:
 
-- Character class intersection and nested negated character classes are unsupported with target `ES2018`. Use target `ES2024` or later if you need support for these features.
+- Character class intersection and nested negated character classes are unsupported with target `ES2018`. Use target `ES2024` (supported by Node.js 20 and 2023-era browsers) or later if you need support for these features.
 - With targets before `ES2025`, a handful of Unicode properties that target a specific character case (ex: `\p{Lower}`) can't be used case-insensitively in patterns that contain other characters with a specific case that are used case-sensitively.
   - In other words, almost every usage is fine, including `A\p{Lower}`, `(?i:A\p{Lower})`, `(?i:A)\p{Lower}`, `(?i:A(?-i:\p{Lower}))`, and `\w(?i:\p{Lower})`, but not `A(?i:\p{Lower})`.
   - Using these properties case-insensitively is basically never done intentionally, so you're unlikely to encounter this error unless it's catching a mistake.
+- Oniguruma-To-ES uses the version of Unicode supported natively by your JavaScript environment. Using Unicode properties via `\p{…}` that require a later version of Unicode than the environment supports results in a runtime error. This is an extreme edge case since modern JavaScript environments support recent versions of Unicode, often ahead of Oniguruma itself.
 
 ## 👀 Similar projects
 
-[JsRegex](https://github.com/jaynetics/js_regex) transpiles [Onigmo](https://github.com/k-takata/Onigmo) regexes to JavaScript (Onigmo is a fork of Oniguruma with mostly shared syntax and behavior). It's written in Ruby and relies on the [Regexp::Parser](https://github.com/ammar/regexp_parser) Ruby gem, which means regexes must be pre-transpiled on the server to use them in JavaScript. Note that JsRegex doesn't always translate edge case behavior differences.
+[JsRegex](https://github.com/jaynetics/js_regex) transpiles [Onigmo](https://github.com/k-takata/Onigmo) regexes to JavaScript (Onigmo is a fork of Oniguruma with similar syntax and behavior). It's written in Ruby and relies on the [Regexp::Parser](https://github.com/ammar/regexp_parser) Ruby gem, which means regexes must be pre-transpiled on the server to use them in JavaScript. Note that JsRegex doesn't always translate edge case behavior differences.
 
 ## 🏷️ About