It's issue 300! I've been sending a weekly CSS Layout News since the 4th August, 2015. If you need a reminder about how very long ago that was, the issue led with the release notes for Chrome 44! I announced Grid Layout shipping in Firefox in issue 84 and Chrome in issue 85, over 4 years ago.
I noted last week, as I was preparing an update to my talk on new things in CSS, how quickly things are shipping into browsers now. Things that I included as coming soon features, have landed in browsers by the time I give the talk again, and new things have started to show up. I started this newsletter to help promote the upcoming grid spec, and it's very cool that there are still plenty of new layout and layout-adjacent things happening to let me make it to issue 300—and beyond!