Fix Apply effects button staying disabled after streaming preview (v1.14.4)

Streaming playback never produces an in-memory blob, but the enable
logic required one. Now enables unconditionally and lazily
re-synthesizes a buffered blob on demand if effects are applied before
one exists.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

CHANGELOG.md

@@ -9,6 +9,13 @@ Follows [Keep a Changelog](https://keepachangelog.com/en/1.0.0/) · versioned wi
 
 ---
 
+## [1.14.4] — 2026-07-08
+
+### Fixed
+- **"Apply effects" button stayed disabled after generating a preview** — streaming playback (the default, lower-latency mode) never produces an in-memory audio blob, and the button's enable logic required one. It now enables regardless of playback mode; if effects are applied before a buffered blob exists, one is synthesized on demand from the same voice/text/instruct/backend used for the preview.
+
+---
+
 ## [1.14.3] — 2026-07-06
 
 ### Added

VERSION

@@ -1 +1 @@
-1.14.3
+1.14.4

static/index.html

@@ -10,7 +10,7 @@
   <meta name="format-detection" content="telephone=no">
   <meta name="color-scheme" content="light dark">
   <meta name="theme-color" content="#2563EB">
-  <meta name="app-version" content="1.14.3">
+  <meta name="app-version" content="1.14.4">
   <link rel="manifest" href="/manifest.webmanifest">
   <link rel="icon" href="/static/icon.svg" type="image/svg+xml">
   <link rel="apple-touch-icon" href="/static/icon.svg">
@@ -27,7 +27,7 @@
 
   <!-- ── Core styles (local — no CDN dependency for first paint) ────────── -->
   <link rel="stylesheet" href="/static/vendor/mdi/materialdesignicons.min.css">
-  <link rel="stylesheet" href="/static/style.css?v=1.14.3">
+  <link rel="stylesheet" href="/static/style.css?v=1.14.4">
 
 
   <!-- ── Flag icons — non-blocking (loaded async, icons appear after JS) ── -->
@@ -365,7 +365,7 @@ window.toggleNavTree = function(treeId, chevronId) {
 </script>
 
 <!-- loader.js: fetches sections → loads JS modules → removes skeleton -->
-<script src="/static/loader.js?v=1.14.3"></script>
+<script src="/static/loader.js?v=1.14.4"></script>
 
 </body>
 </html>

static/js/generation.js

@@ -339,8 +339,6 @@ $('effects-reset-btn')?.addEventListener('click', () => {
 let _effectsSourceBlob = null;
 
 $('effects-apply-btn')?.addEventListener('click', async () => {
-  const blob = previewBlob || _effectsSourceBlob;
-  if (!blob) { toast('Generate audio first', 'error'); return; }
   const chain = [];
   if ($('fx-reverb-on')?.checked)    chain.push({ type:'reverb',      params: { room_size: +$('fx-reverb-room').value, wet: +$('fx-reverb-wet').value, dry: 1 - +$('fx-reverb-wet').value } });
   if ($('fx-compressor-on')?.checked) chain.push({ type:'compressor',  params: { threshold_db: +$('fx-comp-thresh').value, ratio: +$('fx-comp-ratio').value } });
@@ -350,6 +348,13 @@ $('effects-apply-btn')?.addEventListener('click', async () => {
   const btn = $('effects-apply-btn'), st = $('effects-status');
   btn.disabled = true; if (st) st.textContent = 'Processing…';
   try {
+    let blob = previewBlob || _effectsSourceBlob;
+    if (!blob) {
+      const args = window._effectsSynthArgs;
+      if (!args || typeof fetchTtsPreviewBlob !== 'function') { toast('Generate audio first', 'error'); return; }
+      if (st) st.textContent = 'Synthesizing audio…';
+      blob = await fetchTtsPreviewBlob(args.voice, args.text, 'wav', args.instruct, args.backend);
+    }
     const fd = new FormData();
     fd.append('audio', blob, 'audio.wav');
     fd.append('effects', JSON.stringify(chain));

static/js/tts-preview.js

@@ -239,9 +239,16 @@ $('preview-text-area').addEventListener('focus', () => {
   if ($('preview-text-area').value === PREVIEW_SAMPLE_TEXT) $('preview-text-area').value = '';
 }, { once:true });
 
-function _onPreviewGenerated(source, voice, text, backend) {
+function _onPreviewGenerated(source, voice, text, backend, instruct) {
   if (typeof effectsSourceBlob !== 'undefined') window._effectsSourceBlob = null;
-  const ea = $('effects-apply-btn'); if (ea && source.blob) ea.disabled = false;
+  // Streaming playback (the default, lower-latency path) never produces a
+  // blob — audio plays via MSE without ever being fully buffered client-side
+  // — so gating "Apply effects" on source.blob left it permanently disabled
+  // whenever streaming succeeded, which is the common case. Enable it
+  // regardless; the effects handler re-fetches a buffered blob on demand
+  // (see window._effectsSynthArgs) if one isn't already sitting in memory.
+  window._effectsSynthArgs = { voice, text, instruct: instruct || '', backend };
+  const ea = $('effects-apply-btn'); if (ea) ea.disabled = false;
   const ap = $('add-to-playlist-btn'); if (ap && source.blob) ap.disabled = false;
   if (typeof historyPush === 'function' && source.blob) historyPush(voice, text, backend, source.blob, source.url);
 }
@@ -279,7 +286,7 @@ $('preview-btn').addEventListener('click', async () => {
     await audio.play();
     $('save-preview-mp3-btn').disabled = false;
     $('save-preview-btn').disabled = source.streaming;
-    _onPreviewGenerated(source, voice, text, backend);
+    _onPreviewGenerated(source, voice, text, backend, instruct);
     toast(source.streaming ? 'Streaming preview playing' : source.label === 'chunked' ? `Chunked (${text.length} chars) playing` : 'Preview playing', 'success');
   } catch(e) { toast('TTS failed: '+e.message,'error'); }
   finally { $('preview-btn').disabled=false; }