Yes, an Alt-Tab or mission control preview shows a live thumbnail of the whole browser window. Docognito is what makes that thumbnail read as a document rather than a chat. The preview captures the browser's frame as well as the page, so the address bar sits inside it too.
How a window switcher actually captures its picture
Alt-Tab on Windows, Mission Control and Command-Tab on macOS, and similar switchers on Linux all work the same way underneath: the operating system takes a live composite of each open window's surface and lays them out as thumbnails. It is a picture of the window, not a read of the website inside it. Whatever the window is currently drawing gets captured, in real time, the moment you invoke the switcher.
A browser window's surface has two layers stacked on top of each other: the page itself, and the browser's own frame around it, tab strip, address bar and toolbar included. The switcher captures both, because from the operating system's point of view they are one continuous window.
This is also why the preview updates the instant the page does. If a reply is streaming in when you invoke Alt-Tab, the thumbnail shows the document mid-update rather than a frozen snapshot from earlier in the session. The operating system is not choosing a moment to capture. It reads whatever the window is drawing at the instant you ask for the switcher, every time.
What changes in that picture and what does not
| Part of the window | Disguised by Docognito | Captured by the preview |
|---|---|---|
| The page content | Yes, redrawn as a document editor | As a document |
| The browser tab title | Yes | Reflected in the window label some switchers show |
| The tab strip and toolbar | No, this is browser chrome | Shown as normal browser chrome |
| The address bar | No | Still reads claude.ai, chatgpt.com and chat.openai.com, and no other website |
The row that decides what a glance at a preview reveals is the last one. Everything above it changes with the disguise on. The address bar does not.
A second monitor changes none of this. Whether the browser window sits on your main screen or a side display, the switcher still composites the same two layers, page and frame, into the same thumbnail. Moving a window between screens is a placement choice, not a privacy setting.
The address bar sits in the frame, not the page
A full window preview still carries the real address bar
The disguise operates entirely inside the page, so a thumbnail that includes the window's own frame carries the address bar, which still reads claude.ai or chatgpt.com along with it. This is not a gap in the extension. A browser extension has no access to redraw its own chrome, only the page rendered inside it.
Keeping window switching from working against you
Keep the disguised tab in its own window
A browser window holding only the ChatGPT or Claude tab previews as a single clean thumbnail, rather than the last tab you happened to view.
Close windows you are not using
Fewer open windows means fewer thumbnails on screen when you Alt-Tab, and fewer chances for an unrelated window to show something unexpected.
Check the taskbar or dock label too
Some switchers show a short text label alongside the thumbnail. Because the browser tab title is disguised, that label reads as a document title rather than the assistant's name.
Why the tab title still helps here
A window switcher label often comes from the same source as the tab title itself, since the operating system asks the browser for a name to display and the browser hands back whatever the active tab is called. Because the tab title trap rewrites that name before the page can set its own, the label a switcher shows tends to match the document, not the assistant, even in the small text next to the thumbnail.
That is a side effect of one fix reaching two places, not a second feature. The thumbnail image itself is what actually decides what a glance sees, and that is the page content doing the work.
Not every switcher shows a text label at all. Some rely on the thumbnail alone, others show a label only after you hover or hold the key combination for a moment. Where a label does appear, it tends to draw from the same title the taskbar and the browser tab already use, which is exactly the value the disguise rewrites before the page ever sets its own.
What a thumbnail still gives away
A preview thumbnail shows the page exactly as the disguise leaves it, which means it shows a document. What it also shows, because it is a picture of the whole window, is the address bar sitting above that document. If a colleague only glances at a row of thumbnails, the disguise holds. If they stop to read one closely, the address bar is right there.
Use Docognito to keep the page itself reading as a document, and keep the disguised tab in a window of its own so that is the only thing a preview shows.