Sticky Action Bar
Keep the primary actions visible when the page is longer than the screen.
What it adds
A bar that pins the save, submit, or apply actions to the viewport once they would otherwise scroll away.
What your agent is told to do
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What your agent is told to do
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1
Find the long forms and detail pages where the primary action sits below the fold, and pin those actions.
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2
Let the bar sit inline in the normal flow until it is about to leave the viewport, then stick. Reserve its height so nothing shifts at the moment it changes state.
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3
Keep the bar's DOM position fixed in source order so tab order does not change when it sticks. Moving the element on scroll breaks keyboard navigation.
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4
Mirror the real state of the form in the bar: disabled while invalid, pending while saving, hidden when the user has no permission to act.
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5
Do not stack a sticky action bar on top of an existing sticky header, mobile bottom navigation, or cookie banner. Pick one owner of the bottom edge.
Edge cases it handles
6
Edge cases it handles
6- The bar must respect safe-area insets so it clears the iOS home indicator.
- An on-screen keyboard on mobile will fight a bottom-fixed bar — decide whether it rides above the keyboard or unsticks entirely.
- Page content must gain bottom padding equal to the bar's height, or the last field is unreachable.
- If permissions change mid-session, the bar's actions must update, not go stale.
- On short viewports where the bar would take a third of the screen, fall back to inline actions.
- Validation errors summarised in the bar must link to the offending field, not just say the form is invalid.
Definition of done
7
Definition of done
7- The primary action is reachable at any scroll position on a page longer than the viewport.
- Nothing jumps when the bar transitions between inline and stuck.
- Tab order and accessible labels are identical in both states.
- No content is trapped under the bar, including on notched devices.
- Disabled, pending, and no-permission states in the bar match the form's real state.
- 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.