feat: add signed SABR compatibility profiles

SABR_COMPATIBILITY_PROFILES.md

@@ -0,0 +1,160 @@
+# SABR compatibility profiles
+
+SABR compatibility profiles describe volatile WEB and MWEB protocol layouts. They are data, not
+programs. PipePipeExtractor owns the native engine, validates every profile value, and exposes only
+predefined sources, normalized response targets, predicates, and actions.
+
+Profiles cannot perform network requests, read arbitrary process state, inspect media payloads,
+access cookies or PO tokens directly, allocate unbounded state, define functions, or execute code.
+The Host still owns transport, URL validation, request limits, tokens, cookies, UMP framing, media
+assembly, retries, generations, seek, cache, and download behavior.
+
+## Document
+
+The UTF-8 JSON envelope is strict: malformed UTF-8 plus unknown and missing properties are
+rejected. The maximum size is 1 MiB, nesting depth is 16, and structural token count is 8192.
+
+```json
+{
+  "format": 1,
+  "revision": 12,
+  "validFromMs": 1784678400000,
+  "validUntilMs": 1792454400000,
+  "minimumExtractorRevision": 1,
+  "capabilities": [
+    "request-template-v1",
+    "response-schema-v1",
+    "recovery-rules-v1"
+  ],
+  "clients": {
+    "MWEB": {
+      "mediaParts": {"header": 20, "payload": 21, "end": 22},
+      "initialRequest": [
+        {"field": 1, "wireType": "BYTES", "source": "CLIENT_ABR_STATE",
+          "required": true},
+        {"field": 2, "wireType": "BYTES", "source": "SELECTED_FORMATS",
+          "required": false},
+        {"field": 3, "wireType": "BYTES", "source": "BUFFERED_RANGES",
+          "required": false},
+        {"field": 4, "wireType": "VARINT", "source": "PLAYER_TIME_MS",
+          "required": false},
+        {"field": 5, "wireType": "BYTES", "source": "USTREAMER_CONFIG",
+          "required": true},
+        {"field": 16, "wireType": "BYTES", "source": "PREFERRED_AUDIO_FORMATS",
+          "required": false},
+        {"field": 17, "wireType": "BYTES", "source": "PREFERRED_VIDEO_FORMATS",
+          "required": false},
+        {"field": 19, "wireType": "BYTES", "source": "CLIENT_CONTEXT",
+          "required": true}
+      ],
+      "followingRequest": [
+        {"field": 1, "wireType": "BYTES", "source": "CLIENT_ABR_STATE",
+          "required": true},
+        {"field": 2, "wireType": "BYTES", "source": "SELECTED_FORMATS",
+          "required": false},
+        {"field": 3, "wireType": "BYTES", "source": "BUFFERED_RANGES",
+          "required": false},
+        {"field": 4, "wireType": "VARINT", "source": "PLAYER_TIME_MS",
+          "required": false},
+        {"field": 5, "wireType": "BYTES", "source": "USTREAMER_CONFIG",
+          "required": true},
+        {"field": 16, "wireType": "BYTES", "source": "PREFERRED_AUDIO_FORMATS",
+          "required": false},
+        {"field": 17, "wireType": "BYTES", "source": "PREFERRED_VIDEO_FORMATS",
+          "required": false},
+        {"field": 19, "wireType": "BYTES", "source": "CLIENT_CONTEXT",
+          "required": true}
+      ],
+      "responseMappings": [
+        {"partType": 35, "target": "NEXT_REQUEST.BACKOFF_MS", "path": [4],
+          "wireType": "VARINT", "required": false},
+        {"partType": 20, "target": "MEDIA_HEADER.SEQUENCE", "path": [9],
+          "wireType": "VARINT", "required": true}
+      ],
+      "recovery": {
+        "maximumOmissions": 3,
+        "maximumElapsedMs": 15000,
+        "forwardThresholdMs": 30000,
+        "retryDelayMs": 0
+      },
+      "rules": [
+        {"whenAll": ["HAS_ERROR"], "actions": ["FAIL_SESSION"]},
+        {"whenAll": ["RELOAD_REQUESTED"], "actions": ["TRY_RELOAD"]},
+        {"whenAll": ["HAS_PROTECTION_BOUNDARY", "FETCH_SEGMENT_MODE"],
+         "actions": ["REQUIRE_PO_TOKEN", "RETRY"]},
+        {"whenAll": ["HAS_PROTECTION_BOUNDARY", "PUMP_MODE"],
+         "actions": ["REFRESH_PO_TOKEN", "CONTINUE"]},
+        {"whenAll": ["HAS_REDIRECT"], "actions": ["APPLY_REDIRECT", "CONTINUE"]},
+        {"whenAll": [], "actions": ["CONTINUE"]}
+      ]
+    }
+  },
+  "keyId": "current",
+  "signature": "base64-ed25519-signature"
+}
+```
+
+The Ed25519 signature covers the deterministic binary serialization produced by
+`SabrCompatibilityProfile.serialize()`, not the JSON whitespace or property order. A profile is
+accepted only for its validity interval, supported format and capabilities, compatible Extractor
+revision, embedded signing key, and positive monotonic revision.
+
+The canonical payload writes the public client, wire-type, source, target, predicate, and action
+identifiers as UTF-8 strings. It never depends on Java enum ordinals, so adding or reordering an
+internal enum constant cannot silently change an existing signature payload.
+
+## Request templates
+
+Every field has a protobuf number, a matching `VARINT` or `BYTES` wire type, an enum source, and a
+required flag. Initial and following templates are independent and contain at most 64 fields.
+Supported sources are:
+
+- `PLAYER_TIME_MS`
+- `BUFFERED_RANGES`
+- `PLAYBACK_COOKIE`
+- `PO_TOKEN`
+- `SELECTED_FORMATS`
+- `CLIENT_CONTEXT`
+- `CLIENT_ABR_STATE`
+- `USTREAMER_CONFIG`
+- `PREFERRED_AUDIO_FORMATS`
+- `PREFERRED_VIDEO_FORMATS`
+
+The profile receives the encoded value selected by the Host; it never receives an accessor for the
+underlying secret or mutable stream state. The generated request remains subject to the Host's
+256 KiB limit.
+
+## Response mappings
+
+A mapping identifies a UMP part type, a protobuf field path of at most eight elements, an expected
+wire type, and one normalized target. When its UMP part is present, a missing required value fails
+the profile and triggers the circuit breaker. Optional missing values leave the native value
+unchanged.
+
+The native media-header baseline ignores known field numbers whose wire type no longer matches the
+bundled schema before applying profile mappings. This lets a profile deliberately reuse an old
+field number with a new protobuf wire type without failing in the baseline decoder first.
+
+Targets cover next-request timing and playback state, redirects, errors, reload and protection
+signals, plus all normalized media-header properties. Media payload and media-end parts cannot be
+inspected by mappings. Media header, payload, and end UMP types are selected once per session and
+the payload continues through the native streaming collector without JSON or policy evaluation.
+
+## Recovery and behavior
+
+Recovery values are bounded by native limits: at most 16 omissions, 120 seconds elapsed, 300
+seconds forward threshold, and 5 seconds retry delay. Rules contain only known predicates and
+actions, have no loops, and must end in exactly one terminal action. A final unconditional
+`CONTINUE` rule is mandatory.
+
+The Host validates every decision again before applying it. Redirects, token refreshes, retries,
+backoff, reloads, generations, request count, and all other hard limits remain native invariants.
+
+## Compatibility boundary
+
+A profile can adapt known request fields, response paths, UMP media part types, recovery thresholds,
+and combinations of predefined actions. A new transport, cryptographic primitive, token flow,
+media framing model, or Host capability is structural and requires an Extractor release.
+
+A document may carry only WEB or only MWEB. Sessions for a client absent from that valid document
+stay on the bundled native policy without disabling the profile for the client it does cover.

extractor/src/main/java/org/schabi/newpipe/extractor/NewPipe.java

@@ -173,6 +173,7 @@ public static String getYoutubePlayerClient() {
 
     public static void setYoutubePlayerClient(final String youtubePlayerClient) {
         if ("mweb".equals(youtubePlayerClient)
+                || "web".equals(youtubePlayerClient)
                 || "web_safari".equals(youtubePlayerClient)
                 || "android_vr".equals(youtubePlayerClient)
                 || "tv_downgraded".equals(youtubePlayerClient)) {

extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/sabr/BuiltinSabrSessionPolicy.java

@@ -4,7 +4,7 @@
 import java.util.ArrayList;
 import java.util.List;
 
-/** Bundled protocol behavior used when no verified JavaScript policy is active. */
+/** Bundled protocol behavior used when no verified compatibility profile is active. */
 public final class BuiltinSabrSessionPolicy implements SabrSessionPolicy {
     @Nonnull
     @Override