Fix stray promo headers, site-URL subscribing, and YouTube playback

Three reported bugs.

**"West Hawaii today articles get a bunch of stray Trending headers."**
The publisher's widget platform injects promo blocks between the real
paragraphs, inside the article's own container, so every structural
signal tells Readability they belong. What survives is a heading
labelling nothing, because the links under it are filled in by a script
that never runs in the reader. Confirmed on 9 of the 12 articles in
that feed, two each. Blocks marked `data-mrf-recirculation` are now
removed -- the attribute says what the block is for in the widget
platform's own words, which is a better signal than the word
"Trending", since an article may legitimately discuss what is trending.
Nothing longer than a label and a few headlines is ever removed. Also
applied to already-cached articles, in place rather than by discarding
them: the article was fine, only the litter has to go.

**"Can't subscribe to heathercoxrichardson.substack.com."** Adding a
feed handed whatever URL it was given straight to the XML parser, so a
site's home page -- the only URL a reader can actually see and copy --
failed on the root element. That page advertises its feed the way sites
have since 2002, in a <link rel="alternate"> in the head. It is now
read, resolved against the page, and fetched. Only what the page
declares: guessing /feed and /rss would add a burst of 404s to every
failed add and eventually subscribe somebody to the wrong thing.

**"YouTube play is misconfigured."** It was, and YouTube said so: the
player dialog loaded the embed as its own top-level document, which
answers with "Video player configuration error -- Error 153". An embed
has to be embedded. It now sits in an iframe on a minimal host page.
Measured in the app's own WebView: top-level, no requests for the video
stream and the error on screen; framed, the stream loads and there is
no error.

**"Long click on YouTube placeholder should open the URL directly."**
It does now. Worth recording why this is not simply the link's href:
for an image inside a link, WebView's hit test reports the image's URL,
so a long-press on the thumbnail arrives as the i.ytimg.com JPEG. The
video id is resolved out of that.

Verified on a device for all four: the Substack site URL adds "Letters
from an American" and fetches 20 articles; a West Hawaii Today article
extracts with no Trending headers and its body intact; the video plays;
and a long-press reaches the YouTube app.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018AwnALZL6bD4VBtATDVv3B

1 files changed, 30 insertions, 2 deletions

diff --git a/app/src/main/java/org/terst/feedreader/ui/ReaderWebView.kt b/app/src/main/java/org/terst/feedreader/ui/ReaderWebView.kt
index f1400d3..78020a9 100644
--- a/app/src/main/java/org/terst/feedreader/ui/ReaderWebView.kt
+++ b/app/src/main/java/org/terst/feedreader/ui/ReaderWebView.kt
@@ -74,6 +74,11 @@ private fun extractYouTubeVideoId(uri: Uri): String? {
  * WebView's own default long-press behavior (a native "open/copy link" popup) --
  * callers show their own save/share/open action menu instead.
  *
+ * onOpenYouTubeExternally fires for a LONG-press on a YouTube link, with the watch URL, instead
+ * of the ordinary onLongPressLink actions menu -- callers hand it to the system, which is the
+ * YouTube app on a phone that has one. A tap plays the video in the reader; a long-press is how
+ * you say you wanted it somewhere else.
+ *
  * onYouTubeVideo fires for a tap on a YouTube watch link (what ReaderExtractor turns
  * an embedded video into a thumbnail link to) with just the video ID, instead of the
  * old behavior of handing off to the YouTube app/browser -- callers show an in-app
@@ -124,6 +129,7 @@ private fun extractYouTubeVideoId(uri: Uri): String? {
 data class ReaderWebViewCallbacks(
     val onOpenLink: (String) -> Unit,
     val onLongPressLink: (String) -> Unit = {},
+    val onOpenYouTubeExternally: (String) -> Unit = {},
     val onYouTubeVideo: (String) -> Unit = {},
     val onImageTap: (String) -> Unit = {},
     val onScrollChanged: (Int) -> Unit = {},
@@ -245,7 +251,19 @@ fun newReaderWebView(context: Context, callbacks: ReaderWebViewCallbacks): Reade
                 // Every article image now sits inside a zoom link, so a long-press on one
                 // reports that link's internal scheme -- strip it back to the image's own URL
                 // so the actions menu shows, and acts on, something real.
-                callbacks.onLongPressLink(withoutImageZoomScheme(url))
+                val target = withoutImageZoomScheme(url)
+                // A long-press on a video reports the thumbnail's URL rather than the link's --
+                // see youTubeTargetForLongPress, which resolves it back to the video. Straight
+                // out to whatever handles YouTube on the phone, usually the app: a tap already
+                // plays the video in the reader, so the only thing a long-press can usefully
+                // mean is "not in here, out there", and picking that off a menu would be a menu
+                // with one useful item.
+                val video = youTubeTargetForLongPress(target)
+                if (video != null) {
+                    callbacks.onOpenYouTubeExternally(video)
+                } else {
+                    callbacks.onLongPressLink(target)
+                }
                 true
             } else {
                 false
@@ -380,7 +398,17 @@ fun YouTubePlayerDialog(videoId: String, onDismiss: () -> Unit) {
                         }
                     }
                     webChromeClient = WebChromeClient()
-                    loadUrl("https://www.youtube-nocookie.com/embed/$videoId?autoplay=1&playsinline=1")
+                    // A host page with the embed in an iframe, not the embed itself as the
+                    // top-level document. YouTube answers a top-level embed with "Video player
+                    // configuration error -- Error 153", which is the reported "YouTube play is
+                    // misconfigured"; framed, the same URL plays. See YouTubeLinks.
+                    loadDataWithBaseURL(
+                        YOUTUBE_EMBED_BASE_URL,
+                        youTubeEmbedPageHtml(videoId),
+                        "text/html",
+                        "utf-8",
+                        null
+                    )
                 }
             },
             onRelease = { it.destroy() }