Last year, Google swapped Chrome custom tabs for an in-app browser in the Google app for Android. While the new browser was flashier, it was sort of a downgrade as it lacked certain features. It seems like Google is working on improving the experience with a bottom bar in the latest Android beta.
The addition of the bottom bar makes it easier to navigate on today's large-screen phones. It introduces the ability to navigate forwards and backwards with dedicated buttons.
The share button also sits in this bar, and clicking it opens the standard Android share sheet. We also get an overflow menu that gives access to the following options: refresh, open in Chrome (or whichever is your default browser), find in page, browser settings, and send feedback. Unfortunately, the address bar remains at the top.
Apart from the new bottom bar, the in-app browser doesn't look any different; there's a close button on the top-left and a bookmark button on the top-right.
The new bottom bar is apparently rolling out with the latest Google app beta (v11.43) — you can download it from APK Mirror. None of my devices with the update show the new layout just yet, so it might be a while before it rolls out to everyone on the beta channel.