catchouli · Oct 20, 2026 · Oct 20, 2026 · Oct 20, 2026
diff --git a/Cargo.lock b/Cargo.lock
diff --git a/Cargo.toml b/Cargo.toml
@@ -6,7 +6,7 @@ default-members = ["crates/*"]
 
 [workspace.package]
 edition = "2024"
-version = "0.17.0"
+version = "0.18.0"
 license = "MIT"
 
 [profile.release]

diff --git a/README.md b/README.md
@@ -84,7 +84,8 @@ Videos take a few seconds to start, since yt-dlp has to ask YouTube for them fir
 Flex starts on whichever video you have highlighted, so it's usually ready by the time you
 press OK. Hold OK on a video to mark it watched, see related videos or jump to its
 channel. Settings →
-YouTube also has the quality limit (1080p unless you change it), whether to show Shorts
+YouTube also has the quality limit (1080p unless you change it), an H.264 option for
+machines that struggle to decode VP9, whether to show Shorts
 (hidden by default) and which SponsorBlock categories to skip (sponsors, self-promotion
 and "like and subscribe" reminders by default).
 

diff --git a/crates/flex-app/Cargo.toml b/crates/flex-app/Cargo.toml
@@ -9,9 +9,9 @@ anyhow = "1.0.104"
 chrono = { version = "0.4.45", default-features = false, features = ["clock"] }
 eframe = { version = "0.36", default-features = false, features = ["glow", "default_fonts"] }
 env_logger = "0.11.11"
-flex-core = { version = "0.17.0", path = "../flex-core" }
-flex-plugin = { version = "0.17.0", path = "../flex-plugin" }
-flex-web = { version = "0.17.0", path = "../flex-web" }
+flex-core = { version = "0.18.0", path = "../flex-core" }
+flex-plugin = { version = "0.18.0", path = "../flex-plugin" }
+flex-web = { version = "0.18.0", path = "../flex-web" }
 image = { version = "0.25", default-features = false, features = ["jpeg", "png", "webp"] }
 libloading = "0.9"
 log = "0.4.34"

diff --git a/crates/flex-app/src/mpv/mod.rs b/crates/flex-app/src/mpv/mod.rs
@@ -379,7 +379,7 @@ mod tests {
         let _ = env_logger::builder().is_test(true).try_init();
         let tools = flex_core::youtube::Tools::find().expect("yt-dlp in the tools folder or on the PATH");
         let started = Instant::now();
-        let video = tools.resolve("aqz-KE-bpKQ", 1080).unwrap();
+        let video = tools.resolve("aqz-KE-bpKQ", 1080, false).unwrap();
         eprintln!("resolved in {:?}: {} ({:?}p)", started.elapsed(), video.title, video.height);
 
         let mpv = Mpv::headless(&[("vo", "null"), ("ao", "null"), ("hwdec", "no")]).unwrap();

diff --git a/crates/flex-app/src/screens/youtube.rs b/crates/flex-app/src/screens/youtube.rs
@@ -793,7 +793,7 @@ impl Screen for YouTubeSettings {
         if press.is(Action::Back) {
             return Nav::Pop;
         }
-        match self.list.handle(press, 7) {
+        match self.list.handle(press, 8) {
             ListInput::AtTop => Nav::FocusTopBar,
             ListInput::Activate(0) => {
                 let on = !sh.youtube_enabled();
@@ -815,17 +815,22 @@ impl Screen for YouTubeSettings {
                 Nav::None
             }
             ListInput::Activate(3) => {
+                let on = !sh.youtube_h264();
+                sh.set_youtube_h264(on);
+                Nav::None
+            }
+            ListInput::Activate(4) => {
                 let on = !sh.youtube_shorts();
                 sh.set_youtube_shorts(on);
                 Nav::None
             }
-            ListInput::Activate(4) => {
+            ListInput::Activate(5) => {
                 let current = sh.youtube_continue_limit();
                 let i = CONTINUE_LIMITS.iter().position(|n| *n == current).unwrap_or(3);
                 sh.set_youtube_continue_limit(CONTINUE_LIMITS[(i + 1) % CONTINUE_LIMITS.len()]);
                 Nav::None
             }
-            ListInput::Activate(5) => Nav::push(SponsorBlockSettings::default()),
+            ListInput::Activate(6) => Nav::push(SponsorBlockSettings::default()),
             ListInput::Activate(_) => Nav::push(ChannelList::default()),
             ListInput::None => Nav::None,
         }
@@ -847,6 +852,8 @@ impl Screen for YouTubeSettings {
             Row::new(Icon::None, format!("YouTube: {}", if on { "on" } else { "off" })).detail("Adds YouTube to Home"),
             Row::new(Icon::Refresh, tools).detail("OK to update now (they also update daily)"),
             Row::new(Icon::None, format!("Quality: up to {}p", sh.youtube_quality())).detail("OK to change"),
+            Row::new(Icon::None, format!("Codec: {}", if sh.youtube_h264() { "H.264 when available" } else { "any (VP9 or H.264)" }))
+                .detail("H.264 is easier on slow machines · OK to change"),
             Row::new(Icon::None, format!("Shorts: {}", if sh.youtube_shorts() { "shown" } else { "hidden" })).detail("OK to change"),
             Row::new(Icon::None, match sh.youtube_continue_limit() {
                 0 => "Continue Watching: no YouTube videos".to_owned(),

diff --git a/crates/flex-app/src/shared.rs b/crates/flex-app/src/shared.rs
@@ -1641,6 +1641,17 @@ impl Shared {
 
     pub fn set_youtube_quality(&mut self, height: u32) {
         self.set_setting(crate::youtube::QUALITY_SETTING, &height.to_string());
+        self.youtube.forget_streams();
+    }
+
+    /// Whether to prefer H.264 videos (easier to decode than VP9).
+    pub fn youtube_h264(&self) -> bool {
+        self.setting_bool(crate::youtube::H264_SETTING)
+    }
+
+    pub fn set_youtube_h264(&mut self, on: bool) {
+        self.set_setting_bool(crate::youtube::H264_SETTING, on);
+        self.youtube.forget_streams();
     }
 
     pub fn youtube_shorts(&self) -> bool {
@@ -1671,8 +1682,8 @@ impl Shared {
 
     /// Starts finding a video's streams (and what to skip) ahead of playing it.
     pub fn prepare_youtube(&mut self, id: &str) {
-        let (quality, categories) = (self.youtube_quality(), self.sponsorblock_categories());
-        self.youtube.prepare(id, quality, categories);
+        let (quality, h264, categories) = (self.youtube_quality(), self.youtube_h264(), self.sponsorblock_categories());
+        self.youtube.prepare(id, quality, h264, categories);
     }
 
     pub fn yt_channels(&self) -> Vec<flex_core::youtube::store::Channel> {

diff --git a/crates/flex-app/src/youtube.rs b/crates/flex-app/src/youtube.rs
@@ -15,6 +15,8 @@ use flex_core::youtube::{Tools, Video};
 
 pub const ENABLED_SETTING: &str = "youtube";
 pub const QUALITY_SETTING: &str = "youtube_quality";
+/// Whether to prefer H.264, which slow machines decode more easily than VP9.
+pub const H264_SETTING: &str = "youtube_h264";
 pub const SHORTS_SETTING: &str = "youtube_shorts";
 pub const SPONSORBLOCK_SETTING: &str = "youtube_sponsorblock";
 pub const CONTINUE_SETTING: &str = "youtube_continue";
@@ -115,7 +117,7 @@ impl YouTube {
 
     /// Starts finding a video's streams and SponsorBlock segments, unless that's done or
     /// under way. Called when a video is highlighted, so it's usually ready by OK.
-    pub fn prepare(&mut self, id: &str, max_height: u32, categories: Vec<String>) {
+    pub fn prepare(&mut self, id: &str, max_height: u32, h264: bool, categories: Vec<String>) {
         let fresh = self.resolved.get(id).is_some_and(|(at, r)| r.is_ok() && at.elapsed() < RESOLVED_FOR);
         if fresh || self.resolving.contains(id) {
             return;
@@ -125,15 +127,15 @@ impl YouTube {
         self.resolving.insert(id.to_owned());
         let video_id = id.to_owned();
         self.spawn(move |tx| {
-            let mut result = tools.resolve(&video_id, max_height);
+            let mut result = tools.resolve(&video_id, max_height, h264);
             if let Err(e) = &result {
                 // YouTube may have changed something that a newer yt-dlp handles.
                 log::warn!("youtube: {video_id}: {e:#}; checking for a newer yt-dlp");
                 if let Ok(report) = tools::update(true, crate::shared::now_unix())
                     && report.updated.iter().any(|(t, _)| *t == Tool::YtDlp)
                     && let Some(tools) = Tools::find()
                 {
-                    result = tools.resolve(&video_id, max_height);
+                    result = tools.resolve(&video_id, max_height, h264);
                 }
             }
             let _ = tx.send(Msg::Resolved(video_id, result.map_err(|e| format!("{e:#}"))));
@@ -155,6 +157,11 @@ impl YouTube {
         self.resolved.get(id).map(|(_, r)| r)
     }
 
+    /// Forgets every video's streams, after the quality or codec setting changes.
+    pub fn forget_streams(&mut self) {
+        self.resolved.clear();
+    }
+
     /// Forgets a failed attempt so playing again tries again.
     pub fn forget(&mut self, id: &str) {
         if self.resolved.get(id).is_some_and(|(_, r)| r.is_err()) {

diff --git a/crates/flex-core/Cargo.toml b/crates/flex-core/Cargo.toml
@@ -7,7 +7,7 @@ publish = false
 [dependencies]
 anyhow = "1.0.104"
 directories = "6.0.0"
-flex-plugin = { version = "0.17.0", path = "../flex-plugin" }
+flex-plugin = { version = "0.18.0", path = "../flex-plugin" }
 hunch = "2"
 lofty = "0.25.4"
 log = "0.4.34"

diff --git a/crates/flex-core/src/youtube/mod.rs b/crates/flex-core/src/youtube/mod.rs
@@ -72,15 +72,16 @@ impl Tools {
     }
 
     /// Finds the streams for a video (a URL or an 11-character id), at most `max_height`
-    /// pixels tall. Takes a few seconds (it asks YouTube).
-    pub fn resolve(&self, video: &str, max_height: u32) -> Result<Video> {
+    /// pixels tall, and H.264 when `h264` and YouTube has it. Takes a few seconds (it asks
+    /// YouTube).
+    pub fn resolve(&self, video: &str, max_height: u32, h264: bool) -> Result<Video> {
         let url = match video_id(video) {
             Some(id) => format!("https://www.youtube.com/watch?v={id}"),
             None => video.to_owned(),
         };
         let out = self
             .command()
-            .args(["--dump-single-json", "--format", &format_choice(max_height), &url])
+            .args(["--dump-single-json", "--format", &format_choice(max_height, h264), &url])
             .output()
             .with_context(|| format!("running {}", self.yt_dlp.display()))?;
         if !out.status.success() {
@@ -94,9 +95,11 @@ impl Tools {
 
 /// yt-dlp's format choice: the best video up to `max_height` without AV1 (which many
 /// GPUs can't decode, e.g. the TV PC's GTX 1070 Ti), plus the best audio; else the best
-/// single file.
-fn format_choice(max_height: u32) -> String {
-    format!("bv*[vcodec!^=av01][height<={max_height}]+ba/b[height<={max_height}]/b")
+/// single file. With `h264`, H.264 comes first: it's the cheapest to decode, for slow
+/// machines that struggle with VP9.
+fn format_choice(max_height: u32, h264: bool) -> String {
+    let any = format!("bv*[vcodec!^=av01][height<={max_height}]+ba/b[height<={max_height}]/b");
+    if h264 { format!("bv*[vcodec^=avc1][height<={max_height}]+ba/{any}") } else { any }
 }
 
 /// A video ready to play.
@@ -294,7 +297,7 @@ mod tests {
     #[ignore]
     fn resolves_a_real_video() {
         let tools = Tools::find().expect("yt-dlp in the tools folder or on the PATH");
-        let v = tools.resolve("https://www.youtube.com/watch?v=aqz-KE-bpKQ", 1080).unwrap();
+        let v = tools.resolve("https://www.youtube.com/watch?v=aqz-KE-bpKQ", 1080, false).unwrap();
         assert_eq!(v.id, "aqz-KE-bpKQ");
         assert!(v.title.contains("Big Buck Bunny"), "{}", v.title);
         assert!(v.audio_url.is_some() && v.height.is_some_and(|h| h <= 1080));

diff --git a/crates/flex-core/src/youtube/proxy.rs b/crates/flex-core/src/youtube/proxy.rs
@@ -362,7 +362,7 @@ mod tests {
     #[ignore]
     fn relays_youtube_fast() {
         let tools = super::super::Tools::find().expect("yt-dlp");
-        let video = tools.resolve("aqz-KE-bpKQ", 1080).unwrap();
+        let video = tools.resolve("aqz-KE-bpKQ", 1080, false).unwrap();
         let local = global().unwrap().add(&video.video_url, video.video_size);
         let started = std::time::Instant::now();
         let response = ureq::get(&local).header("Range", "bytes=0-").call().unwrap();

diff --git a/crates/flex-web/Cargo.toml b/crates/flex-web/Cargo.toml
@@ -7,7 +7,7 @@ publish = false
 [dependencies]
 anyhow = "1.0.104"
 axum = "0.8.9"
-flex-core = { version = "0.17.0", path = "../flex-core" }
+flex-core = { version = "0.18.0", path = "../flex-core" }
 log = "0.4.34"
 serde = { version = "1.0.229", features = ["derive", "rc"] }
 serde_json = "1.0.151"

diff --git a/plugins/anilist/Cargo.toml b/plugins/anilist/Cargo.toml
@@ -7,5 +7,5 @@ license.workspace = true
 publish = false
 
 [dependencies]
-flex-plugin = { version = "0.17.0", path = "../../crates/flex-plugin" }
+flex-plugin = { version = "0.18.0", path = "../../crates/flex-plugin" }
 ureq = { version = "3", features = ["json"] }
diff --git a/plugins/anilist/plugin.toml b/plugins/anilist/plugin.toml
@@ -1,6 +1,6 @@
 name = "AniList"
 description = "Updates your AniList progress as you watch anime in Flex"
-version = "0.17.0"
+version = "0.18.0"
 command = "flex-anilist"
 subscribe = ["playback"]
 

diff --git a/plugins/lotus-lamp/Cargo.toml b/plugins/lotus-lamp/Cargo.toml
@@ -7,6 +7,6 @@ license.workspace = true
 publish = false
 
 [dependencies]
-flex-plugin = { version = "0.17.0", path = "../../crates/flex-plugin" }
+flex-plugin = { version = "0.18.0", path = "../../crates/flex-plugin" }
 lotus-lamp = { git = "https://github.com/bombpersons/lotus-lamp-rs", rev = "59cf5ccaa0007f006f1812fd02cc5991aff11e72" }
 tokio = { version = "1.53.2", features = ["rt", "time", "sync", "macros"] }
diff --git a/plugins/lotus-lamp/plugin.toml b/plugins/lotus-lamp/plugin.toml
@@ -1,6 +1,6 @@
 name = "LED strip (Lotus Lamp)"
 description = "Lights a Bluetooth LED strip behind the TV with the colours on screen"
-version = "0.17.0"
+version = "0.18.0"
 command = "flex-lotus-lamp"
 subscribe = ["light"]
 

diff --git a/plugins/trakt/Cargo.toml b/plugins/trakt/Cargo.toml
@@ -7,5 +7,5 @@ license.workspace = true
 publish = false
 
 [dependencies]
-flex-plugin = { version = "0.17.0", path = "../../crates/flex-plugin" }
+flex-plugin = { version = "0.18.0", path = "../../crates/flex-plugin" }
 ureq = { version = "3", features = ["json"] }
diff --git a/plugins/trakt/plugin.toml b/plugins/trakt/plugin.toml
@@ -1,6 +1,6 @@
 name = "Trakt"
 description = "Keeps your Trakt history up to date with what you watch in Flex"
-version = "0.17.0"
+version = "0.18.0"
 command = "flex-trakt"
 subscribe = ["playback"]