Bug 7400 - Clicking in Web Access with multiple mouse buttons simultaneously doesn't work in Chrome and Edge
Summary: Clicking in Web Access with multiple mouse buttons simultaneously doesn't wor...
Status: NEW
Alias: None
Product: ThinLinc
Classification: Unclassified
Component: Web Access (show other bugs)
Version: trunk
Hardware: PC Unknown
: P2 Normal
Target Milestone: LowPrio
Assignee: Bugzilla mail exporter
URL: https://github.com/novnc/noVNC/issues...
Depends on:
Reported: 2019-10-11 16:46 CEST by Samuel Mannehed
Modified: 2021-11-18 15:46 CET (History)
1 user (show)

See Also:
Acceptance Criteria:


Description Samuel Mannehed cendio 2019-10-11 16:46:58 CEST
While holding a click with one mouse button and simultaneously clicking with another mouse button will result in that the second mouse click never gets through.

Steps to reproduce the behavior:

1. Connect using Web Access
2. Monitor mouse events using 'xev' in a terminal inside the session
3. Press the left mouse button but don't release it
4. Click with the right mouse button
5. Release the left mouse button
6. Observe that the right click never gets sent to the session

Found the problem with ThinLinc build 6262 in Chrome 77 on Fedora 30. Verified that the problem doesn't exist in Firefox 69.

Also tested ThinLinc 4.10.1 and saw that the problem was even worse before - using the same steps as above additionally the left mouse button 'up'-event never got through. This caused the left mouse button to get hanged with 4.10.1, both on Firefox and Chrome.
Comment 1 Samuel Mannehed cendio 2019-10-11 16:47:51 CEST
The remaining problem with build 6262 is likely related to our SetCapture() emulation, seeing as it isn't used on Firefox.
Comment 2 Pierre Ossman cendio 2020-06-12 15:52:31 CEST
Edge (pre-Chromium) seems to also have bugs here. We never get a mousedown for the first press of the right mouse button in the above scenario. We get a mouseup after releasing it though, and after that we can get a mousedown. Very strange.
Comment 3 Samuel Mannehed cendio 2021-11-17 17:20:19 CET
Let's test this with the new Edge.
Comment 4 Frida cendio 2021-11-18 13:54:21 CET
I can verify that this is still an issue with new Edge and Chrome, but not Firefox.

Tested ThinLinc server 4.13.0post (build 2350) and webaccess in the following browsers on Windows 10:
* Microsoft Edge Version 95.0.1020.5
* Google Chrome Version 96.0.4664.45
* Firefox 94.0.1

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