Collapsible Sections
Let users fold away the parts of a crowded page they do not need right now.
What it adds
Sections with a heading that expands and collapses, so a long page can be reduced to the parts in use.
What your agent is told to do
5
What your agent is told to do
5-
1
Find the pages carrying several distinct groups of content and give each group a real heading plus a disclosure control.
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2
Make the whole heading row the trigger, using a native button with the correct expanded state exposed, and render the collapsed content in a way that is genuinely removed from tab order and screen reader flow.
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3
Choose sensible defaults per section rather than collapsing everything — a page that opens fully collapsed is a page with no content.
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4
When a validation error, a search match, or a deep link targets content inside a collapsed section, expand that section and scroll to the target.
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5
Do not collapse required actions, blocking warnings, or anything the user must act on. Hiding a problem behind a chevron does not solve it.
Edge cases it handles
6
Edge cases it handles
6- Persisted expansion state must be discarded when the section no longer exists or the user's permissions have changed.
- Browser find-in-page cannot search collapsed content — accept this and make section headings descriptive enough to find.
- Collapsing a section containing focus must move focus to the section heading, not lose it.
- The animation must respect prefers-reduced-motion, and must not be applied to sections restored as collapsed on first paint.
- A section whose content is empty should say so rather than expanding into nothing.
- Sections that are expanded on load must not shift layout after data arrives — reserve space or keep them collapsed until loaded.
Definition of done
8
Definition of done
8- Every section has an accessible trigger reporting its expanded state.
- Collapsed content is out of tab order and hidden from assistive technology.
- Validation errors, deep links, and search hits auto-expand their section.
- Warnings and required actions are never collapsible.
- Focus is handled deliberately when a section closes.
- Animation respects prefers-reduced-motion and does not run on initial paint.
- The feature matches the existing design system.
- No existing functionality is broken.
Related features
Beautiful Empty States
Beautiful Empty States
Replace blank screens with useful, contextual empty states.
What it does
Every list, table, and dashboard in your app has a "nothing here yet" state. Most
apps ship a blank rectangle — and it is often the very first thing a new user sees.
An empty state should say what belongs here, why it is empty, and what to do next.
How it works
- 1 Inventory the empty cases first. List every collection view in the app and
- 2 Distinguish the three kinds of empty. They are not the same, and must not
- 3 Build one reusable empty-state component from the existing design system,
Copy the prompt
No account needed
Add this feature to my app:
https://addthisfeature.com/x/beautiful-empty-states
Countdown Timer
Countdown Timer
A live countdown to a deadline that ends cleanly instead of running negative.
What it does
A countdown component driven by a server-provided deadline, with a defined finished state.
How it works
- 1 Send the deadline and the server's current time together, compute the offset between server and device once, and count against the corrected value. The device clock cannot be trusted to be right.
- 2 Recompute the remaining time from the corrected clock on every tick rather than decrementing a stored number, so a suspended tab does not resume showing a value minutes behind reality.
- 3 Define the finished state explicitly: what the component shows at zero, whether it reveals something, disables a control, or triggers a refetch. Reuse the app's existing Progress Indicator System styling rather than introducing new type and colour for the digits.
Copy the prompt
No account needed
Add this feature to my app:
https://addthisfeature.com/x/countdown-timer
Expandable Text
Expandable Text
Shorten long text without making the full content hard to reach.
What it does
Long text clamped to a few lines, with an explicit control to show the rest and collapse it again.
How it works
- 1 Clamp by rendered lines, not by character count. Cutting a string at a fixed length breaks words, mangles markup, and truncates differently at every width.
- 2 Only show the expand control when the text is genuinely clipped. A 'Show more' on a two-line paragraph is noise.
- 3 Use a real button with an accessible label naming what expands, and expose the expanded state. An untagged 'more...' is invisible to a screen reader.
Copy the prompt
No account needed
Add this feature to my app:
https://addthisfeature.com/x/expandable-text
How it works
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1
Copy the link
Grab the Markdown instruction URL for this feature.
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2
Give it to your AI
Paste it into Claude Code, Cursor, v0, Lovable — whatever you build with.
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3
It inspects, then implements
Your agent reads your existing app first, then adds the feature to fit it.
Works with your stack
These instructions are written to adapt. They tell the agent to detect your framework, match your existing design system, and reuse what you already have — rather than assuming a particular stack.
Need it tighter than that? Customize the feature and tell it exactly what you're running.