UserAgent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/54.0.2816.0 Safari/537.36

Steps to reproduce the problem:
1. Navigate to https://bugs.chromium.org/p/chromium/issues/list
2. Mouse left-drag to highlight any text (e.g. "1 - 100")
3. In another terminal, run [xsel -p] to dump the PRIMARY X11 selection

What is the expected behavior?
xsel prints the highlighted string.

What went wrong?
xsel prints whatever PRIMARY held before the mouse-highlight event.

Did this work before? Yes 52 stable

Chrome version: 54.0.2816.0  Channel: beta
OS Version: goobuntu 14.04
Flash Version: Shockwave Flash 23.0 r0

Ctrl-C still correctly copies to CLIPBOARD and also populates PRIMARY.

Highlighting text using the keyboard in an input textbox (e.g. using shift-arrows) still correctly populates PRIMARY.
Selecting all text on a page with Ctrl-A does NOT populate PRIMARY.