Why does flexbox not work in Opera?

Question

Opera

Good afternoon.
Why does flexbox not work in Opera?
To demonstrate the bug, please open the link in Opera !!!
And that's what we have. (

But in Chrome and Mazil everything is OK!

If you disable the parent - .box-text-text -- display: flex;
then in Opera everything is satisfactory

Why?
And you can even not in caniuse.com walk... it's flexes and the year 2019!!!
Prefixes - don't help.
Thanks!
P/S Gentlemen, please kindly - before making superficial decisions and voting that the question is "simple" (... well , which can be difficult in flex, it's not angular) you Please - publish your "simple" solutions, confirm your theses!
Ok`)

Answer 1

opera flight normal

Answer 2