From e1adc7c1aff5e014275a946e7946cee2b2121b4e Mon Sep 17 00:00:00 2001
From: diondiondion <mail@diondiondion.com>
Date: Tue, 15 Sep 2026 14:49:32 +0000
Subject: [PATCH] Redesign: Implement new navigation in advanced (multi-column)
 layout (#40522)

---
 .../mastodon/components/column/index.tsx      |  7 ++++-
 .../components/column/styles.module.scss      | 19 +++++++++++++
 .../columns_area/multi_column_content.tsx     |  5 ++++
 .../columns_area/redesign.module.scss         | 28 ++++++++++++++-----
 .../ui/components/columns_area/redesign.tsx   | 19 ++++++-------
 .../redesign_multicol.module.scss             | 28 +++++++++++++++++++
 6 files changed, 87 insertions(+), 19 deletions(-)
 create mode 100644 app/javascript/mastodon/components/column/styles.module.scss
 create mode 100644 app/javascript/mastodon/features/ui/components/columns_area/redesign_multicol.module.scss

diff --git a/app/javascript/mastodon/components/column/index.tsx b/app/javascript/mastodon/components/column/index.tsx
index 380136e24ee..4a55652eb24 100644
--- a/app/javascript/mastodon/components/column/index.tsx
+++ b/app/javascript/mastodon/components/column/index.tsx
@@ -5,9 +5,11 @@ import classNames from 'classnames';
 import { useDebouncedCallback } from 'use-debounce';
 
 import { getColumnSkipLinkId } from '@/mastodon/features/ui/components/skip_links';
+import { isRedesignEnabled } from '@/mastodon/utils/environment';
 import { scrollTop } from 'mastodon/scroll';
 
 import { ColumnContext, useColumnIndexContext } from './context';
+import classes from './styles.module.scss';
 
 interface ColumnProps {
   children?: React.ReactNode;
@@ -66,7 +68,10 @@ export const Column: React.FC<ColumnProps> = ({
       role='region'
       ref={nodeRef}
       onScroll={handleScroll}
-      className={classNames('column', className)}
+      className={classNames(
+        isRedesignEnabled() ? classes.root : 'column',
+        className,
+      )}
       aria-label={label}
       aria-labelledby={
         label === undefined ? getColumnSkipLinkId(columnIndex) : undefined
diff --git a/app/javascript/mastodon/components/column/styles.module.scss b/app/javascript/mastodon/components/column/styles.module.scss
new file mode 100644
index 00000000000..3e4e70bc9ba
--- /dev/null
+++ b/app/javascript/mastodon/components/column/styles.module.scss
@@ -0,0 +1,19 @@
+:global(.layout-multiple-columns) .root {
+  box-sizing: border-box;
+  position: relative;
+  display: flex;
+  flex-direction: column;
+  flex: 0 0 auto;
+
+  --available-width: calc(
+    100% - var(--multi-column-navigation-width) - var(--multi-column-gap)
+  );
+
+  width: clamp(
+    360px,
+    (var(--available-width) / 4 - var(--multi-column-gap)),
+    400px
+  );
+  padding: 0;
+  background: var(--color-bg-primary);
+}
diff --git a/app/javascript/mastodon/features/ui/components/columns_area/multi_column_content.tsx b/app/javascript/mastodon/features/ui/components/columns_area/multi_column_content.tsx
index 957d9d13f3f..f3267c52587 100644
--- a/app/javascript/mastodon/features/ui/components/columns_area/multi_column_content.tsx
+++ b/app/javascript/mastodon/features/ui/components/columns_area/multi_column_content.tsx
@@ -4,6 +4,7 @@ import type { List, Record } from 'immutable';
 
 import { ColumnIndexContext } from '@/mastodon/components/column/context';
 import { useAppSelector } from '@/mastodon/store';
+import { isRedesignEnabled } from '@/mastodon/utils/environment';
 
 import {
   Compose,
@@ -76,6 +77,10 @@ export const MultiColumnContent: React.FC<{
         const uuid = column.get('uuid');
         const id = column.get('id');
 
+        if (isRedesignEnabled() && id === 'COMPOSE') {
+          return null;
+        }
+
         return (
           <ColumnIndexContext.Provider value={index} key={uuid}>
             <Bundle
diff --git a/app/javascript/mastodon/features/ui/components/columns_area/redesign.module.scss b/app/javascript/mastodon/features/ui/components/columns_area/redesign.module.scss
index 4f388e7e411..b4716a03ed9 100644
--- a/app/javascript/mastodon/features/ui/components/columns_area/redesign.module.scss
+++ b/app/javascript/mastodon/features/ui/components/columns_area/redesign.module.scss
@@ -6,7 +6,6 @@
   --navigation-max-width: 320px;
 
   box-sizing: border-box;
-  display: flex;
   width: 100%;
   height: 100%;
   min-height: 100vh;
@@ -33,6 +32,19 @@
   --navigation-min-width: 0;
 }
 
+.multiColumnRoot {
+  --multi-column-navigation-width: 320px;
+  --multi-column-gap: var(--space-xs);
+
+  position: relative;
+  display: flex;
+  flex: 1 1 auto;
+  justify-content: flex-start;
+  gap: var(--multi-column-gap);
+  padding-inline-end: var(--multi-column-gap);
+  overflow-x: auto;
+}
+
 .navigationWrapper {
   position: sticky;
   top: 0;
@@ -41,6 +53,14 @@
   height: 100dvh;
   padding-bottom: env(safe-area-inset-bottom);
 
+  .multiColumnRoot & {
+    height: initial;
+    min-width: var(--multi-column-navigation-width);
+    inset-inline-start: 0;
+    z-index: 100;
+    background: var(--color-bg-blend);
+  }
+
   @media (max-width: ($mobile-menu-breakpoint - 1)) {
     display: none;
   }
@@ -58,12 +78,6 @@
   color: var(--color-text-primary);
   background-color: var(--color-bg-primary);
 
-  :global(.column) {
-    width: 100%;
-    height: 100%;
-    padding: 0;
-  }
-
   :global(.scrollable) {
     contain: content;
     overflow: visible;
diff --git a/app/javascript/mastodon/features/ui/components/columns_area/redesign.tsx b/app/javascript/mastodon/features/ui/components/columns_area/redesign.tsx
index cc41887e363..b92d167618d 100644
--- a/app/javascript/mastodon/features/ui/components/columns_area/redesign.tsx
+++ b/app/javascript/mastodon/features/ui/components/columns_area/redesign.tsx
@@ -3,13 +3,13 @@ import classNames from 'classnames';
 import { ComposeRedesignButton } from '@/mastodon/features/compose/redesign/trigger';
 import { RedesignNavigationPanel } from '@/mastodon/features/navigation_panel/redesign';
 import { RedesignMobileNavigation } from '@/mastodon/features/navigation_panel/redesign/mobile_nav';
-import { useAppSelector } from '@/mastodon/store';
 import { Footer } from 'mastodon/features/custom_homepage/components/footer';
 
 import { useBreakpoint } from '../../hooks/useBreakpoint';
 
 import { MultiColumnContent } from './multi_column_content';
 import classes from './redesign.module.scss';
+import multiColClasses from './redesign_multicol.module.scss';
 
 export const ColumnsAreaRedesign: React.FC<{
   singleColumn?: boolean;
@@ -17,14 +17,11 @@ export const ColumnsAreaRedesign: React.FC<{
   children: React.ReactElement | React.ReactElement[];
   ref?: React.Ref<HTMLDivElement>;
 }> = ({ children, minimalShell, singleColumn, ref }) => {
-  const isModalOpen = useAppSelector(
-    (state) => !state.modal.get('stack').isEmpty(),
-  );
   const isMobile = useBreakpoint('openable');
 
   if (minimalShell) {
     return (
-      <div className={classNames(classes.root, classes.rootMinimal)}>
+      <div ref={ref} className={classNames(classes.root, classes.rootMinimal)}>
         {isMobile && <RedesignMobileNavigation />}
         <div className={classes.main}>
           <div>{children}</div>
@@ -37,7 +34,7 @@ export const ColumnsAreaRedesign: React.FC<{
 
   if (singleColumn) {
     return (
-      <div className={classes.root}>
+      <div ref={ref} className={classes.root}>
         <div className={classes.navigationWrapper}>
           <RedesignNavigationPanel />
         </div>
@@ -49,11 +46,11 @@ export const ColumnsAreaRedesign: React.FC<{
   }
 
   return (
-    <main
-      className={classNames('columns-area', { unscrollable: isModalOpen })}
-      ref={ref}
-      tabIndex={isModalOpen ? undefined : 0}
-    >
+    <main ref={ref} className={multiColClasses.root}>
+      <div className={multiColClasses.navigationWrapper}>
+        <RedesignNavigationPanel />
+      </div>
+      <ComposeRedesignButton />
       <MultiColumnContent>{children}</MultiColumnContent>
     </main>
   );
diff --git a/app/javascript/mastodon/features/ui/components/columns_area/redesign_multicol.module.scss b/app/javascript/mastodon/features/ui/components/columns_area/redesign_multicol.module.scss
new file mode 100644
index 00000000000..33aa871dbac
--- /dev/null
+++ b/app/javascript/mastodon/features/ui/components/columns_area/redesign_multicol.module.scss
@@ -0,0 +1,28 @@
+@use '@/styles/mastodon/variables' as *;
+
+.root {
+  --multi-column-navigation-width: 320px;
+  --multi-column-gap: var(--space-xs);
+
+  position: relative;
+  display: flex;
+  flex: 1 1 auto;
+  justify-content: flex-start;
+  gap: var(--multi-column-gap);
+  padding-inline-end: var(--multi-column-gap);
+  overflow-x: auto;
+}
+
+.navigationWrapper {
+  position: sticky;
+  inset-inline-start: 0;
+  top: 0;
+  z-index: 100;
+  min-width: var(--multi-column-navigation-width);
+  padding-bottom: env(safe-area-inset-bottom);
+  background: var(--color-bg-blend);
+
+  @media (max-width: ($mobile-menu-breakpoint - 1)) {
+    display: none;
+  }
+}