diff --git a/edit.html b/edit.html
index 05936741..8dd7cf5e 100644
--- a/edit.html
+++ b/edit.html
@@ -418,17 +418,15 @@
           <summary><h2 i18n-text="sections"></h2></summary>
           <ol id="toc"></ol>
         </details>
-        <details id="lint" data-pref="editor.lint.expanded" class="hidden-unless-compact ignore-pref-if-compact">
+        <details id="lint" data-pref="editor.lint.expanded" class="ignore-pref-if-compact" hidden>
           <summary>
-            <h2 i18n-text="linterIssues">: <span id="issue-count"></span>
+            <h2><span i18n-text="linterIssues"></span><span id="issue-count"></span>
               <a id="lint-help" class="svg-inline-wrapper intercepts-click" tabindex="0">
                 <svg class="svg-icon info"><use xlink:href="#svg-icon-help"/></svg>
               </a>
             </h2>
           </summary>
-          <div class="lint-scroll-container">
-            <div class="lint-report-container"></div>
-          </div>
+          <div class="lint-report-container"></div>
         </details>
       </div>
       <div id="header-resizer" i18n-title="headerResizerHint"></div>
diff --git a/edit/base.js b/edit/base.js
index a42b5f65..0e9afaf5 100644
--- a/edit/base.js
+++ b/edit/base.js
@@ -6,14 +6,7 @@
 /* global initBeautifyButton */// beautify.js
 /* global prefs */
 /* global t */// localization.js
-/* global
-  FIREFOX
-  debounce
-  getOwnTab
-  sessionStore
-  tryJSONparse
-  tryURL
-*/// toolbox.js
+/* global FIREFOX getOwnTab sessionStore tryJSONparse tryURL */// toolbox.js
 'use strict';
 
 /**
@@ -56,6 +49,13 @@ const editor = {
 
 const baseInit = (() => {
   const domReady = waitForSelector('#sections');
+  const mq = matchMedia('(max-width: 850px)');
+  (mq.onchange = e => {
+    document.documentElement.classList.toggle('compact-layout', e.matches);
+    for (const el of $$('details[data-pref]')) {
+      el.open = e.matches ? false : prefs.get(el.dataset.pref);
+    }
+  })(mq);
 
   return {
     domReady,
@@ -120,45 +120,6 @@ const baseInit = (() => {
   }
 })();
 
-//#endregion
-//#region init layout/resize
-
-baseInit.domReady.then(() => {
-  let headerHeight;
-  detectLayout(true);
-  window.on('resize', () => detectLayout());
-
-  function detectLayout(now) {
-    const compact = window.innerWidth <= 850;
-    if (compact) {
-      document.body.classList.add('compact-layout');
-      if (!editor.isUsercss) {
-        if (now) fixedHeader();
-        else debounce(fixedHeader, 250);
-        window.on('scroll', fixedHeader, {passive: true});
-      }
-    } else {
-      document.body.classList.remove('compact-layout', 'fixed-header');
-      window.off('scroll', fixedHeader);
-    }
-    for (const el of $$('details[data-pref]')) {
-      el.open = compact ? false : prefs.get(el.dataset.pref);
-    }
-  }
-
-  function fixedHeader() {
-    const headerFixed = $('.fixed-header');
-    if (!headerFixed) headerHeight = $('#header').clientHeight;
-    const scrollPoint = headerHeight - 43;
-    if (window.scrollY >= scrollPoint && !headerFixed) {
-      $('body').style.setProperty('--fixed-padding', ` ${headerHeight}px`);
-      $('body').classList.add('fixed-header');
-    } else if (window.scrollY < scrollPoint && headerFixed) {
-      $('body').classList.remove('fixed-header');
-    }
-  }
-});
-
 //#endregion
 //#region init header
 
diff --git a/edit/edit.css b/edit/edit.css
index 2bad83a1..e771619e 100644
--- a/edit/edit.css
+++ b/edit/edit.css
@@ -1,5 +1,6 @@
 :root {
-  --fixed-padding: unset;
+  --pad: 1rem;
+  --pad05: calc(0.5 * var(--pad));
 }
 
 body {
@@ -70,7 +71,7 @@ html:not(.is-new-style) #heading::after {
 #popup-button:hover {
   filter: drop-shadow(0 0 3px hsl(180, 70%, 50%));
 }
-.usercss body:not(.compact-layout) #popup-button {
+.usercss:not(.compact-layout) #popup-button {
   right: 24px;
 }
 /************ checkbox & select************/
@@ -91,10 +92,10 @@ label {
 #header {
   width: var(--header-width);
   height: 100vh;
-  overflow: auto;
+  overflow: hidden;
   position: fixed;
   top: 0;
-  padding: 1rem;
+  padding-top: var(--pad);
   box-shadow: 0 0 3rem -1.2rem black;
   box-sizing: border-box;
   z-index: 10;
@@ -222,56 +223,61 @@ input:invalid {
   margin-left: 0;
 }
 /* collapsibles */
+#header details {
+  margin-right: var(--header-resizer-width);
+}
+#header details[open] {
+  overflow-y: auto;
+  margin-top: calc(1.5*var(--pad));
+}
+#header details[open] summary {
+  position: absolute;
+  margin-top: calc(-1.5*var(--pad));
+}
 #header summary {
   align-items: center;
-  margin-left: -13px;
+  margin-left: .25em;
   cursor: pointer;
-}
-#header summary + * {
-  padding: .5rem 0;
+  white-space: nowrap;
 }
 #header summary h2 {
   display: inline-block;
   border-bottom: 1px dotted transparent;
-  margin-top: .1em;
-  margin-bottom: .1em;
-  margin-left: -13px;
+  margin: 0 0 0 -13px;
   padding-left: 13px; /* clicking directly on details-marker doesn't set pref so we cover it with h2 */
+  max-width: calc(var(--header-width) - 2*var(--pad));
+  vertical-align: middle;
+}
+#header summary h2,
+#header summary h2 > :first-child {
+  white-space: nowrap;
+  overflow: hidden;
+  text-overflow: ellipsis;
 }
-
 #header summary:hover h2 {
   border-color: #bbb;
 }
-
 #header summary svg {
   margin-top: -3px;
 }
-
+#header details > :not(summary) {
+  margin: 0 0 0 var(--pad);
+  padding: calc(var(--pad)/4) 0;
+}
 #details-wrapper {
   display: flex;
   flex-direction: column;
   flex-grow: 1;
+  overflow: hidden;
+  margin-top: var(--pad05);
 }
-
-#header details[open] + details[open] {
-  margin-top: .5rem;
-}
-
 #actions .buttons {
   display: inline-flex;
   flex-wrap: wrap;
   align-items: center;
 }
-
 #actions .buttons > * {
-  margin: 0 .25rem .5rem 0;
-}
-
-#options:not([open]) + #lint h2 {
-  margin-top: 0;
-}
-#lint:not([open]) h2 {
-  margin-bottom: 0;
+  margin: 0 .25rem var(--pad05) 0;
 }
 
 #publish > div > * {
@@ -426,8 +432,6 @@ input:invalid {
 }
 #toc {
   counter-reset: codelabel;
-  margin: 0;
-  padding: .5rem 0;
 }
 #toc li {
   white-space: nowrap;
@@ -829,40 +833,13 @@ body:not(.find-open) [data-match-highlight-count="1"] .CodeMirror-selection-high
 
 /************ lint ************/
 #lint {
-  overflow: hidden;
-  margin-left: -1rem;
-  margin-right: -1rem;
-  padding: 0;
-  box-sizing: border-box;
-  display: flex;
-  flex-grow: 1;
-  position: relative;
-}
-#lint > summary {
-  position: relative;
-  margin-left: 0;
-  padding-left: 4px;
-}
-#lint[open]:not(.hidden-unless-compact) {
-  min-height: 102px;
-}
-#lint summary h2 {
-  text-indent: -2px;
-}
-#lint > .lint-scroll-container {
-  margin: 1rem 10px 0;
-  position: absolute;
-  top: 0;
-  bottom: 0;
-  left: 0;
-  right: 0;
-  overflow-y: auto;
   overflow-x: hidden;
 }
+#lint summary h2 {
+  display: inline-flex;
+}
 #lint table {
-  font-size: 100%;
   border-spacing: 0;
-  margin-bottom: 1rem;
   line-height: 1.0;
   width: 100%;
 }
@@ -878,7 +855,7 @@ body:not(.find-open) [data-match-highlight-count="1"] .CodeMirror-selection-high
 #lint table.empty {
   display: none;
 }
-#lint caption {
+#lint caption:not(:empty) {
   text-align: left;
   font-weight: bold;
   padding-bottom: 6px;
@@ -908,6 +885,9 @@ body:not(.find-open) [data-match-highlight-count="1"] .CodeMirror-selection-high
   text-align: left;
   white-space: nowrap;
 }
+#issue-count::before {
+  content: ':\A0';
+}
 #message-box.center.lint-config #message-box-contents {
   text-align: left;
 }
@@ -970,11 +950,6 @@ html:not(.usercss) .usercss-only,
   display: none !important; /* hide during page init */
 }
 
-body:not(.compact-layout) .hidden-unless-compact,
-body.linter-disabled .hidden-unless-compact {
-  display: none !important;
-}
-
 #options:not([open]) + #lint {
   margin-top: 0;
 }
@@ -1021,152 +996,100 @@ body.linter-disabled .hidden-unless-compact {
   margin-left: 0.2rem;
 }
 
+/************ full-width only ************/
+/* TODO: maybe move more rules here so we don't need to reset them in @media(max-width: 850px) */
+@media (min-width: 851px) {
+  #header > :not(#details-wrapper):not(#header-resizer) {
+    margin-left: var(--pad);
+    margin-right: var(--pad);
+  }
+  #publish[open],
+  #header details:not([open]) {
+    flex: 0 0 auto;
+  }
+  #header details[open]:not(:last-child) {
+    margin-bottom: var(--pad05);
+  }
+  #header details:last-child {
+    padding-bottom: var(--pad);
+  }
+}
+
 /************ reponsive layouts ************/
 @media(max-width: 850px) {
-  body {
+  html:not(.usercss) body {
+    height: 100%;
+  }
+  .usercss body {
     display: flex;
     flex-direction: column;
   }
+  .usercss #header {
+    position: inherit;
+  }
   #header {
-    flex: 0 1 auto;
+    display: block;
+    flex: 0 0 auto;
     height: unset;
     width: unset;
-    position: inherit;
+    position: sticky;
+    background: #fff;
     border-right: none;
     border-bottom: 1px dashed #AAA;
-    padding: .5rem 1rem .5rem .5rem;
-  }
-  .fixed-header {
-    --fixed-height: 40px;
-    padding-top: var(--fixed-padding);
-  }
-  .fixed-header #header {
-    min-height: var(--fixed-height);
-    position: fixed;
-    top: 0;
-    left: 0;
-    right: 0;
-    padding: 0;
-    background-color: #fff;
-  }
-  .fixed-header #header > *:not(#details-wrapper),
-  .fixed-header #options {
-    display: none !important;
-  }
-  .fixed-header #details-wrapper {
-    padding-top: calc((var(--fixed-height) - 1.2rem) / 2); /* 1.2 is the normal line height */
-  }
-  #header summary + *,
-  #lint > .lint-scroll-container {
-    margin-left: 1rem;
-    padding: .25rem 0 .5rem;
-  }
-  #header input[type="checkbox"] {
-    vertical-align: middle;
-  }
-  #header details {
-    margin: 0;
+    padding: var(--pad05) var(--pad05) 0;
   }
   #heading,
   h2 {
     display: none;
   }
   #basic-info {
-    margin-bottom: .5rem;
+    margin: 0 16px var(--pad05) 0; /* for popup icon in simple window */
     box-sizing: border-box;
     display: flex;
     flex-wrap: wrap;
   }
+  #basic-info #name,
   #basic-info > *:first-child {
     flex-grow: 1;
   }
   #basic-info > *:not(:last-child) {
     margin-right: 0.8rem;
   }
-  #basic-info #name {
-    flex-grow: 1;
+  #header details > :not(summary) {
+    margin-left: var(--pad05);
   }
-  #options-wrapper {
-    display: flex;
-    flex-wrap: wrap;
-    box-sizing: border-box;
+  #header h2 {
+    font-size: 14px;
+  }
+  #actions {
+    display: inline-block;
   }
   #details-wrapper {
+    display: inline-flex;
+    vertical-align: top;
+    max-width: 100%;
     flex-direction: row;
-    flex-wrap: wrap;
+    margin: .25em 0 var(--pad05);
   }
-  #options[open] {
-    width: 100%;
+  #details-wrapper details[open] {
+    max-height: 10vh;
   }
-  #sections-list[open] {
-    max-height: 102px;
-  }
-  #sections-list[open] #toc {
-    max-height: 60px;
-    overflow-y: auto;
-  }
-  #header details:not(#options) {
+  #details-wrapper[data-open^=".."] details {
     max-width: 50%;
   }
-  .options-column {
-    flex-grow: 1;
-    padding-right: .5rem;
-    box-sizing: border-box;
+  #details-wrapper[data-open^="..."] {
+    flex-wrap: wrap;
   }
-  .options-column > .usercss-only {
-    margin-bottom: 0;
-  }
-  #options-wrapper .options-column:nth-child(2) {
-    margin-top: 0;
-  }
-  #options:not([open]),
+  #options[open],
+  #publish[open],
   #lint:not([open]) {
-    overflow: initial;
-  }
-  #options:not([open]) + #lint:not([open]) {
-    margin-top: 0;
-  }
-  #lint summary {
-    position: static;
-    margin-bottom:  0;
-  }
-  #header summary {
-    margin-left: 0;
-    padding-left: 4px;
-  }
-  #header summary h2 {
-    margin: 0;
-    padding: 0;
-  }
-  .option label {
-    margin: 0;
-  }
-  #options [type="number"] {
-    text-align: left; /* workaround the column flow bug in webkit */
-    padding-left: 0.2rem;
-  }
-  #options #tabSize-label {
-    position: relative;
-    top: 0.2rem;
-  }
-  #lint > .lint-scroll-container {
-    padding-top: 0;
-    margin-right: 0;
-  }
-  #lint {
-    padding: 0;
-    margin: .5rem 0 0;
-  }
-  #lint:not([open]) + #footer {
-    margin: .25em 0 -1em .25em;
+    flex: 0 0 auto;
+    overflow-x: hidden;
   }
   #sections {
-    height: unset !important;
     padding-left: 0;
-    display: flex;
-    flex-direction: column;
-    flex: 1;
   }
+  /* TODO: switch from .single-editor to the global .usercss */
   #sections > :not(.single-editor) {
     margin: 0 .5rem;
     padding: .5rem 0;
@@ -1175,10 +1098,6 @@ body.linter-disabled .hidden-unless-compact {
     overflow: hidden;
     flex: 1;
   }
-  .usercss #options:not([open]) ~ #lint.hidden ~ #footer,
-  .usercss #lint:not([open]) + #footer {
-    margin-top: -.25em;
-  }
   #help-popup.big[style="display: block;"],
   #help-popup[style="display: block;"] {
     width: max-content;
diff --git a/edit/edit.js b/edit/edit.js
index 64e5c0ea..89a945b5 100644
--- a/edit/edit.js
+++ b/edit/edit.js
@@ -1,4 +1,4 @@
-/* global $ $create messageBoxProxy waitForSheet */// dom.js
+/* global $$ $ $create messageBoxProxy waitForSheet */// dom.js
 /* global API msg */// msg.js
 /* global CodeMirror */
 /* global SectionsEditor */
@@ -43,6 +43,19 @@ baseInit.ready.then(async () => {
   new MutationObserver(() => elSec.open && editor.updateToc())
     .observe(elSec, {attributes: true, attributeFilter: ['open']});
 
+  // Auto-update `data-open` attribute to the number of open details
+  {
+    const wrapper = $('#details-wrapper');
+    const details = $$('details', wrapper);
+    const ds = wrapper.dataset;
+    const update = () => {
+      ds.open = '.'.repeat(details.reduce((res, el) => res + (el.open ? 1 : 0), 0));
+    };
+    for (const el of details) {
+      new MutationObserver(update).observe(el, {attributes: true, attributeFilter: ['open']});
+    }
+  }
+
   $('#toc').onclick = e =>
     editor.jumpToEditor([...$('#toc').children].indexOf(e.target));
   $('#keyMap-help').onclick = () =>
diff --git a/edit/linter-manager.js b/edit/linter-manager.js
index a4c26751..d6b65a71 100644
--- a/edit/linter-manager.js
+++ b/edit/linter-manager.js
@@ -312,7 +312,7 @@ linterMan.DEFAULTS = {
   function updateCount() {
     const issueCount = Array.from(tables.values())
       .reduce((sum, table) => sum + table.trs.length, 0);
-    $('#lint').classList.toggle('hidden-unless-compact', issueCount === 0);
+    $('#lint').hidden = !issueCount;
     $('#issue-count').textContent = issueCount;
   }
 
diff --git a/global.css b/global.css
index cbb92c9e..8af35744 100644
--- a/global.css
+++ b/global.css
@@ -277,13 +277,15 @@ input[type="number"][data-focused-via-click]:focus {
 /* header resizer */
 :root {
   --header-width: 280px;
+  --header-resizer-width: 8px;
 }
 #header-resizer {
   position: absolute;
   top: 0;
   right: 0;
   bottom: 0;
-  width: 6px;
+  width: var(--header-resizer-width);
+  box-sizing: border-box;
   cursor: e-resize;
   border-width: 0 1px;
   border-style: solid;
diff --git a/manifest.json b/manifest.json
index a6a4ef9b..c0e75c0c 100644
--- a/manifest.json
+++ b/manifest.json
@@ -1,7 +1,7 @@
 {
   "name": "Stylus",
   "version": "1.5.22",
-  "minimum_chrome_version": "55",
+  "minimum_chrome_version": "56",
   "description": "__MSG_description__",
   "homepage_url": "https://add0n.com/stylus.html",
   "manifest_version": 2,