Or, just as frequent an occurrence, your pointy haired boss wears glasses instead of a tie, and nothing else has really changed.
The grass sure looks greener on the other side, but unless you work for some truly heartless pond scum, you'll find a lot in common between any two employers.
I've learned over the years that it really comes down to do a ton of due diligence on the company. It's easier now with LinkedIn, Glassdoor and other sites that allow you to get a glimpse of what some employees think of the company. I also found that you can use LinkedIn to search for that company, and you can spend some time viewing profiles for former developers or another role you're wanting to take on. If you see that a handful of developers have left under a year while at that company and are doing a similar role at another company that's a red flag to me. I'd reach out to those developers and just get their honest opinion.
This isn't always possible, but it has ended up with my last two employers being some of the best I ever had.
The grass sure looks greener on the other side, but unless you work for some truly heartless pond scum, you'll find a lot in common between any two employers.