fix(web): task lists in formatted text line up with the other items

The box takes the bullet's place instead of the whole item moving left,
and it is no longer `disabled` (browsers grey those out): it keeps the
brand colour, out of reach of clicks and the keyboard.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

libs/web/tracker/presenters/src/lib/ui/markdown.spec.ts

@@ -43,7 +43,17 @@ describe('renderMarkdown', () => {
 
   it('shows task lists as ticked boxes nobody can click', () => {
     const html = renderMarkdown('- [x] Reproducido\n- [ ] Arreglado');
-    expect(html).toContain('<input checked="" disabled="" type="checkbox">');
+    const boxes = Array.from(
-    expect(html).toContain('<input disabled="" type="checkbox">');
+      new DOMParser()
+        .parseFromString(html, 'text/html')
+        .querySelectorAll<HTMLInputElement>('input[type="checkbox"]'),
+    );
+    expect(boxes.map((box) => box.checked)).toEqual([true, false]);
+    // Not `disabled` (browsers grey those out): out of reach instead.
+    for (const box of boxes) {
+      expect(box.disabled).toBe(false);
+      expect(box.getAttribute('aria-disabled')).toBe('true');
+      expect(box.tabIndex).toBe(-1);
+    }
   });
 });

libs/web/tracker/presenters/src/lib/ui/markdown.ts

@@ -67,9 +67,14 @@ function installHooks(): void {
       }
     }
     if (node.tagName === 'INPUT') {
-      // Task lists: `- [x] done` renders as a ticked, read-only box.
+      // Task lists: `- [x] done` renders as a ticked box nobody can change.
+      // Not `disabled`: browsers grey those out; CSS takes the clicks away.
       if (node.getAttribute('type') !== 'checkbox') node.remove();
-      else node.setAttribute('disabled', '');
+      else {
+        node.removeAttribute('disabled');
+        node.setAttribute('aria-disabled', 'true');
+        node.setAttribute('tabindex', '-1');
+      }
     }
     const cls = node.getAttribute('class');
     if (cls && !/^ts-mention( is-me)?$/.test(cls))
@@ -117,7 +122,8 @@ export function renderMarkdown(text: string, me: string | null = null): string {
       'data-user',
       'type',
       'checked',
-      'disabled',
+      'aria-disabled',
+      'tabindex',
     ],
     // DOMPurify's own rule plus `attachment:`: links and images to http(s),
     // mail or a pasted file; plain values (`type="checkbox"`) still pass.
@@ -179,10 +185,20 @@ export const MARKDOWN_STYLES = `
           margin: 0;
         }
       }
+      /* Task items: the box takes the bullet's place, so their text lines
+         up with the other items' (as in the editor). */
       li:has(> input[type='checkbox']),
       li:has(> p:first-child > input[type='checkbox']) {
         list-style: none;
-        margin-left: -1.375rem;
+      }
+      li > input[type='checkbox'],
+      li > p:first-child > input[type='checkbox'] {
+        width: 0.875rem;
+        height: 0.875rem;
+        margin: 0 0.25rem 0 -1.375rem;
+        vertical-align: -0.125em;
+        accent-color: var(--ts-brand);
+        pointer-events: none;
       }
       a {
         color: var(--ts-brand);