Fallback writing sidebar for broken extension sessions

When an AI writing extension freezes mid-sentence — Chrome hanging, the sidebar collapsed, the suggestion panel gone — most users do one of two things: they abandon the AI assist entirely and write manually, or they open a new tab to the full web editor and copy-paste back and forth. Both options are described explicitly in the complaints here, and both are expensive in terms of interrupted flow.

The underlying problem is that every AI writing tool is built around a single delivery mechanism — the extension — with no graceful degradation path. If the extension breaks, the session is over. There's no lightweight fallback that persists independently of the extension's health. The vendors don't build one because it would mean maintaining two surfaces, and they're incentivized to make the extension look reliable rather than admit it isn't.

What a writer actually needs in that moment is a small, durable window — something closer to a sticky notepad than a full editor — that stays accessible regardless of what the extension is doing on the host page. It should pull from the same AI backend they're already subscribed to but operate as a separate process that doesn't share the extension's service worker or content script lifecycle. They paste in the text they were struggling with, get the rewrite or suggestion, and paste it back. Ugly, but functional.

This is a business because it's not competing with the AI writing tools — it's a reliability layer that sits on top of them. The buyer is a writer who pays $15–40/month for an AI writing tool and finds it unreliable enough that they'd pay a few dollars more for a session that doesn't randomly collapse. The need recurs every time Chrome updates, every time the host site changes its CSP, every time the extension vendor ships a bad build.

What to build

Build a lightweight standalone Chrome side panel app (using the Chrome Side Panel API, which runs outside content script scope) that connects to a user's existing AI writing tool API key and provides rewrite, rephrase, and tone suggestions without depending on the extension's content script injection — persistent across tab switches and page reloads.

Where to start

Launch specifically for users of tools that expose a public API and have documented extension reliability complaints — position it as the session that keeps working when your main tool doesn't, and distribute it through communities like r/freelancewriters where extension frustration is a recurring thread topic.

The hard part

Connecting to a user's existing AI writing tool API key requires that the vendor exposes a documented API with reasonable rate limits — several tools in this category do not offer public API access, which forces you to either build your own AI layer (different product) or narrow the target to tools that do.

How it makes money

Flat monthly subscription of $5–8, with a free trial of 50 requests to demonstrate the reliability difference before charging.