What happened to my Tildes bookmark on my Android phone?

I'm using an Android phone with Chrome 65.0.3325.109 installed.

There's an option in this browser to add a page to the home screen. This creates a shortcut on my home screen. When I tap on that shortcut, it opens the saved page in Chrome.

I had done this with Tildes. However, I deleted the shortcut and made it again. The behaviour has now changed.

Previously, this shortcut opened Tildes as a tab within Chrome. Now, it opens Tildes as its own separate "application". It's not in Chrome. That means I don't get the functionality that comes with Chrome, such as opening a link in a new Chrome tab. In this pseudo-application version, I'm stuck with only one window. I can't open other tabs. I can't simply copy links from one Chrome tab (news website) to another Chrome tab (Tildes).

Did you change something in the past week or so? Can you please change it back? I want a shortcut to a web page to open something that behaves like a web page, not a stand-alone application.