diff --git a/doc/RFC.md b/doc/RFC.md
index a227f36..148bc81 100644
--- a/doc/RFC.md
+++ b/doc/RFC.md
@@ -4,7 +4,7 @@
 
 > version 1.0.0
 
-date: 2023-04-06T18:31:24+0200<br>
+date: 2023-04-06T18:37:15+0200<br>
 [![Actions Status](https://github.com/coderofsalvation/xrfragment/workflows/test/badge.svg)](https://github.com/coderofsalvation/xrfragment/actions)
 
 # XRFragment Grammar 
@@ -23,7 +23,8 @@ date: 2023-04-06T18:31:24+0200<br>
 | Explanation | |
 |-|-|
 | `x=1,2,3` | vector/coordinate argument e.g. |
-| `x=foo\|bar\|1\,2,3\|1.0` | the `\|` character is used for:<br>1.specifying `n` arguments for xrfragment `x`<br>2. fallback urls (`src=https://x.co/f.gltf\|xyz://f.gltf`)<br>3. roundrobin of values (in case provided arguments exceeds `n` of `x` for #1) when triggered by browser URI (clicking `href` e.g.)|
+| `x=foo\|bar|1,2,3|1.0` | the `\|` character is used for:<br>1.specifying `n` arguments for xrfragment `x`<br>2. roundrobin of values (in case provided arguments exceeds `n` of `x` for #1) when triggered by browser URI (clicking `href` e.g.)|
+| `https://x.co/1.gltf||xyz://x.co/1.gltf` | multi-protocol/fallback urls  |
 | `.mygroup` | query-alias for `class:mygroup` |
 
 > Focus: hasslefree 3D vector-data (`,`), multi-protocol/fallback-linking & dynamic values (`|`), and CSS-piggybacking (`.mygroup`) 
diff --git a/src/xrfragment/URI.hx b/src/xrfragment/URI.hx
index b4b73ac..0f20597 100644
--- a/src/xrfragment/URI.hx
+++ b/src/xrfragment/URI.hx
@@ -27,7 +27,8 @@ import xrfragment.Parser;
  * | Explanation | |
  * |-|-|
  * | `x=1,2,3` | vector/coordinate argument e.g. |
- * | `x=foo\|bar\|1\,2,3\|1.0` | the `\|` character is used for:<br>1.specifying `n` arguments for xrfragment `x`<br>2. fallback urls (`src=https://x.co/f.gltf\|xyz://f.gltf`)<br>3. roundrobin of values (in case provided arguments exceeds `n` of `x` for #1) when triggered by browser URI (clicking `href` e.g.)|
+ * | `x=foo\|bar|1,2,3|1.0` | the `\|` character is used for:<br>1.specifying `n` arguments for xrfragment `x`<br>2. roundrobin of values (in case provided arguments exceeds `n` of `x` for #1) when triggered by browser URI (clicking `href` e.g.)|
+ * | `https://x.co/1.gltf||xyz://x.co/1.gltf` | multi-protocol/fallback urls  |
  * | `.mygroup` | query-alias for `class:mygroup` |
  *
  * > Focus: hasslefree 3D vector-data (`,`), multi-protocol/fallback-linking & dynamic values (`|`), and CSS-piggybacking (`.mygroup`)