expose style name

_locales/en/messages.json

@@ -1085,6 +1085,12 @@
     "message": "Exposes the top site domain in each iframe.\nEnables writing iframe-specific CSS like this:\nhtml[stylus-iframe$$=\"twitter.com\"] h1 { display:none }",
     "description": "Add attribute to iframe; make sure to include the double $$ in the css example, or the `$=` will be omitted in the displayed text."
   },
+  "optionsAdvancedExposeStyleName": {
+    "message": "Expose style name"
+  },
+  "optionsAdvancedExposeStyleNameNote": {
+    "message": "Exposes the style name in the page to facilitate debugging of styles in devtools. Please reload the tab(s) to apply the new setting."
+  },
   "optionsAdvancedNewStyleAsUsercss": {
     "message": "Write new style as usercss"
   },

background/style-manager.js

@@ -184,6 +184,7 @@ const styleMan = (() => {
           },
         };
       }
+      const {exposeStyleName} = prefs.__values;
       const sender = CHROME && this && this.sender || {};
       if (sender.frameId === 0) {
         /* Chrome hides text frament from location.href of the page e.g. #:~:text=foo
@@ -202,9 +203,9 @@ const styleMan = (() => {
       } else if (cache.maybeMatch.size) {
         buildCache(cache, url, Array.from(cache.maybeMatch, id2data).filter(Boolean));
       }
-      return id
-        ? cache.sections[id] ? {[id]: cache.sections[id]} : {}
-        : Object.assign({cfg: {order}}, cache.sections);
+      return Object.assign({cfg: {exposeStyleName, order}},
+        id ? mapObj(cache.sections, null, [id])
+          : cache.sections);
     },
 
     /** @returns {Promise<StyleObj>} */
@@ -429,7 +430,7 @@ const styleMan = (() => {
       const code = getAppliedCode(createMatchQuery(url), style);
       if (code) {
         updated.add(url);
-        cache.sections[id] = {id, code};
+        buildCacheEntry(cache, style, code);
       } else {
         excluded.add(url);
         delete cache.sections[id];
@@ -703,13 +704,20 @@ const styleMan = (() => {
     for (const {style, appliesTo, preview} of styleList) {
       const code = getAppliedCode(query, preview || style);
       if (code) {
-        const id = style.id;
-        cache.sections[id] = {id, code};
+        buildCacheEntry(cache, style, code);
         appliesTo.add(url);
       }
     }
   }
 
+  function buildCacheEntry(cache, style, code = style.code) {
+    cache.sections[style.id] = {
+      code,
+      id: style.id,
+      name: style.customName || style.name,
+    };
+  }
+
   /** @returns {StyleObj[]} */
   function getAllAsArray() {
     return Array.from(dataMap.values(), v => v.style);

background/style-via-webrequest.js

@@ -1,5 +1,5 @@
 /* global API */// msg.js
-/* global CHROME ignoreChromeError */// toolbox.js
+/* global CHROME URLS ignoreChromeError */// toolbox.js
 /* global prefs */
 'use strict';
 
@@ -49,6 +49,12 @@
     if (CHROME && !off) {
       chrome.webNavigation.onCommitted.addListener(injectData, {url: [{urlPrefix: 'http'}]});
     }
+    if (CHROME) {
+      chrome.webRequest.onBeforeRequest.addListener(openNamedStyle, {
+        urls: [URLS.ownOrigin + '*.user.css'],
+        types: ['main_frame'],
+      }, ['blocking']);
+    }
     state.csp = csp;
     state.off = off;
     state.xhr = xhr;
@@ -146,6 +152,12 @@
     }
   }
 
+  /** @param {chrome.webRequest.WebRequestBodyDetails} req */
+  function openNamedStyle(req) {
+    chrome.tabs.update(req.tabId, {url: 'edit.html?id=' + req.url.split('#')[1]});
+    return {cancel: true};
+  }
+
   function req2key(req) {
     return req.tabId + ':' + req.frameId;
   }

content/apply.js

@@ -105,7 +105,6 @@
       if (styles.cfg) {
         isDisabled = styles.cfg.disableAll;
         Object.assign(order, styles.cfg.order);
-        delete styles.cfg;
       }
       hasStyles = !isDisabled;
       if (hasStyles) {
@@ -181,7 +180,6 @@
         if (!hasStyles && isDisabled || matchUrl === request.url) break;
         matchUrl = request.url;
         API.styles.getSectionsByUrl(matchUrl).then(sections => {
-          delete sections.cfg;
           hasStyles = true;
           styleInjector.replace(sections);
         });

content/style-injector.js

@@ -11,10 +11,12 @@ window.StyleInjector = window.INJECTED === 1 ? window.StyleInjector : ({
   const ORDERED_TAGS = new Set(['head', 'body', 'frameset', 'style', 'link']);
   const docRewriteObserver = RewriteObserver(_sort);
   const docRootObserver = RootObserver(_sortIfNeeded);
+  const toSafeChar = c => String.fromCharCode(0xFF00 + c.charCodeAt(0) - 0x20);
   const list = [];
   const table = new Map();
   let isEnabled = true;
   let isTransitionPatched;
+  let exposeStyleName;
   // will store the original method refs because the page can override them
   let creationDoc, createElement, createElementNS;
 
@@ -83,7 +85,7 @@ window.StyleInjector = window.INJECTED === 1 ? window.StyleInjector : ({
   };
 
   function _add(style) {
-    const el = style.el = _createStyle(style.id, style.code);
+    const el = style.el = _createStyle(style);
     const i = list.findIndex(item => compare(item, style) > 0);
     table.set(style.id, style);
     if (isEnabled) {
@@ -116,18 +118,18 @@ window.StyleInjector = window.INJECTED === 1 ? window.StyleInjector : ({
         !styles.some(s => s.code.includes('transition'))) {
       return;
     }
-    const el = _createStyle(PATCH_ID, `
+    const el = _createStyle({id: PATCH_ID, code: `
       :root:not(#\\0):not(#\\0) * {
         transition: none !important;
       }
-    `);
+    `});
     document.documentElement.appendChild(el);
     // wait for the next paint to complete
     // note: requestAnimationFrame won't fire in inactive tabs
     requestAnimationFrame(() => setTimeout(() => el.remove()));
   }
 
-  function _createStyle(id, code = '') {
+  function _createStyle({id, code = '', name} = {}) {
     if (!creationDoc) _initCreationDoc();
     let el;
     if (document.documentElement instanceof SVGSVGElement) {
@@ -145,6 +147,11 @@ window.StyleInjector = window.INJECTED === 1 ? window.StyleInjector : ({
       const oldEl = document.getElementById(el.id);
       if (oldEl) oldEl.id += '-superseded-by-Stylus';
     }
+    if (exposeStyleName && name) {
+      el.dataset.name = name;
+      name = encodeURIComponent(name.replace(/[#%/@:']/g, toSafeChar));
+      code += `\n/*# sourceURL=${chrome.runtime.getURL('')}${name}.user.css#${id} */`;
+    }
     el.type = 'text/css';
     // SVG className is not a string, but an instance of SVGAnimatedString
     el.classList.add('stylus');
@@ -224,9 +231,12 @@ window.StyleInjector = window.INJECTED === 1 ? window.StyleInjector : ({
   }
 
   function _styleMapToArray(styleMap) {
-    return Object.values(styleMap).map(s => ({
-      id: s.id,
-      code: s.code.join(''),
+    ({exposeStyleName} = styleMap.cfg || {});
+    delete styleMap.cfg;
+    return Object.values(styleMap).map(({id, code, name}) => ({
+      id,
+      name,
+      code: code.join(''),
     }));
   }
 

js/prefs.js

@@ -24,6 +24,7 @@
     'show-badge': true,             // display text on popup menu icon
     'disableAll': false,            // boss key
     'exposeIframes': false,         // Add 'stylus-iframe' attribute to HTML element in all iframes
+    'exposeStyleName': false,       // Add style name to the style for better devtools experience
     'newStyleAsUsercss': false,     // create new style in usercss format
     'styleViaXhr': false,           // early style injection to avoid FOUC
     'patchCsp': false,              // add data: and popular image hosting sites to strict CSP

options.html

@@ -269,6 +269,18 @@
               <span></span>
             </span>
           </label>
+          <label>
+            <span i18n-text="optionsAdvancedExposeStyleName">
+              <a i18n-title="optionsAdvancedExposeStyleNameNote"
+                 data-cmd="note" class="svg-inline-wrapper" tabindex="0">
+                <svg class="svg-icon info"><use xlink:href="#svg-icon-help"/></svg>
+              </a>
+            </span>
+            <span class="onoffswitch">
+              <input type="checkbox" id="exposeStyleName" class="slider">
+              <span></span>
+            </span>
+          </label>
           <label class="chromium-only">
             <span i18n-text="optionsAdvancedContextDelete"></span>
             <span class="onoffswitch">