Now that you mention it, I didn't realize that change as well when I stopped using safari. My (uneducated) guess is that it's probably a browser difference, not sure if there's a way to change it or not... I can mostly just advice you to bookmark whichever chapter you left off on to keep track. Also if you usually stay logged into your account in the same browser window, you can click the history button in the upper right corner (it's between the search and notification bell) it shows you the exact chapter and page you initially left off on—which may not always be accurate if you go back to reread a chapter, but it's still an option.
i'm pretty sure the history syncs to each login. I've been able to see history from what I read on my tablet on my phone. it just has a limit of like 2 weeks.
Normally when you read a chapter, it gets shaded to show that you’ve already read it, which helps track your reading history. It used to work for me on Safari, but when I switched to Chrome, it isn’t working, and the chapters aren’t being shaded, it’ll show in my history but it won’t become shaded so it’s really annoying. Does anyone know how to fix this?