I am fully aware that there is no way for a user to port an app that runs on Blackberry somewhere else, if not for some compatibility problems then Blackberry's strong security and encryption features stand against it. But it means that Opera could make a such a port with much less effort needed than a port of a native app would imply....
Btw. my Blackberry Q10 can do both: Android and native apps, and both could be Java..., and so far I have found no way to tell what exactly runs there... My old Samsung would indicate a running JRE with an icon, but the BB doesn't.
Sometimes, clicking a link just reloads the page. When this happens, opening the page in a new tab usually works instead.
Please provide an exact page where this happens and which link do you click.
Upgraded Unicode support would be nice, not least for emojis.
Characters are drawn using what is available on your phone in most cases. If you don't see some emoji, then most likely your phone simply doesn't have one, what is quite often the case on feature phones to save memory.
The other two issues would require J2ME client changes, which is unlikely to happen soon.
Since Opera Mini for Windows Phone has stopped its development the app has been retired from the Store, just users with Opera Mini installed before could access it.
I have access but I don't have my Lumia jailbroken and don't know if even with jailbrake it's possible to export it to be installed in another device...
Writing those lines...
Now I remember that I had installed a Xap file (I think) from XDA Developers, if you search and find the Opera Mini Xap file enabling Developer tools into your Lumia 630 maybe that way you could install it.
At the other hand, try asking in XDA Developers, you'll find a better answer on how to install it if possible.