Safari redirects local sites to https after update to 10.13.2

Same here, exact the same behavior. (.dev domain, since today, Chrome works, etc...). It seems not to be related to MAMP, as I have a different setup, though. As a workaround, I switched form .dev to .local, which mitigates the problem, but is annoying.

possibly related:

https://iyware.com/dont-use-dev-for-development/

Long and short is .dev is now a generic Top Level Domain owned in full by Google.

.local, .test, .example should all work.

There are some indications that a new browser release for Chrome will also look for a certificate and/or redirect to https.

This is clearly an evolving issue. ymmv.

I thought I was going mad! As a website developer, I can no longer load any of my local sites, except those with a valid SSL certificate.

I have the same issue in other browsers, not just Safari.

Does anybody know why this is happening?

I seem to recall this happening before, a few years ago. Suddenly after an OS X update (as it was called back then), locally-defined domains no longer resolved correctly. Eventually Apple fixed this, so that /etc/hosts is checked first, as it should be.

Same exact issue on 2 macs.
Running apache 2.
The 10.13.2 update forced me to redo .conf files. & hosts

Firefox (quantum), Chrome fine

Same issue on Safari Technology Preview browser

Seriously? .dev is now an official TLD? Well, there goes my muscle memory! I only have.... 100 sites! ...set up this way!

Thanks for the explanation.

.test is also reserved, apparently.

More info:

https://iyware.com/dont-use-dev-for-development/

I think you misread that.
.test and .local should remain safe as development tld's
(they are reserved for just that purpose)