wbroom

Browser screen share failed: black screen and empty picker

Confirm the picker and OS recording permission first. If a share is already on, stop it. Still black? Debug the path or use the board.

They see a black rectangle, or the browser window list is empty. A failed browser screen share is usually the picker, macOS recording permission, or a share that is already live.

For browser screen share failed, split the fault: did you confirm a window, tab, or screen; does this browser have Screen Recording; is someone else already sharing?

Confirm the picker OS screen-recording permission One share and the network

Four usual causes

01

The picker opened and you dismissed it

Chrome, Edge, Safari, and Firefox ask you to pick a window, a tab, or the whole screen. Closing the dialog means no track starts.

02

macOS has not allowed this browser to record the screen

System Settings → Privacy & Security → Screen Recording, or Screen & System Audio Recording. After you enable the browser, quit it fully (⌘+Q, not just the window) and reopen.

03

Another share is already on

wbroom allows one live screen share at a time. Ask them to stop, then start yours.

04

You are presenting from a phone or an IDE preview

Mobile browsers limit capture. Embedded editor previews often cannot see a display. Present from a system desktop browser; join by phone to listen.

Four steps in order

  1. 1

    Open the room in a system browser

    Create or join from the wbroom homepage. Steps: create and join a room. Do not join from an editor preview.

  2. 2

    Pick one target and confirm

    After Screen share, select a window, tab, or screen and confirm. Notes: screen share not working.

  3. 3

    Grant OS recording permission, then restart the browser

    On macOS, enable Chrome / Edge / Safari / Firefox, quit fully, and rejoin the same room ID. On Windows, check that a work policy is not blocking desktop capture.

  4. 4

    If it stays black, debug the path or use the board

    Picker and permission look fine but nobody sees pixels: firewall or VPN — WebRTC connection troubleshooting. Sketch boxes on the board instead. Phones: mobile browser.

1 share
Only one screen share at a time
0 accounts
OS permission is not restored by signup
8 max
People per room — skip 4K desktops on weak links

Which layer first

Symptom Check first On wbroom
Empty picker or it vanishes macOS recording permission; full browser quit Grant, restart, rejoin the same room ID
Preview is black for you and for them Protected external display or HDR screen Share a normal window or a browser tab
Click does nothing Someone else is already sharing Stop that share, then start yours
Voice works; video never starts VPN, corporate network, stale browser Follow WebRTC help, or switch to the board

Product limits on the features page: voice first, screen and camera on demand. The room ID is the credential. For reviews, see design review.

Let the OS accept this browser as a recorder before you blame the room. If the picker was not confirmed, the room never sees a track.

# Local checks before you recreate the room
# 1) System browser (not an IDE preview)
# 2) Picker: window / tab / screen + Confirm
# 3) macOS: Screen Recording = on, then ⌘Q the browser
One share
A second click is blocked on purpose. That is a room rule, not a dead room ID.
The board can stand in
Boxes and arrows on a shared canvas often beat a frozen 4K desktop.

Still deciding?

Do I need an account to share the screen?

No. wbroom uses a room ID. The grant is to this browser in the OS, not to a login.

Are Safari and Chrome settings the same?

The menus differ. On macOS both need their own row under Screen Recording / Screen & System Audio Recording. Quit that browser after you change it.

Why is sharing so hard on a phone?

OS and mobile browsers restrict capture more tightly. Join by phone to listen; present from a desktop browser.

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