Vivaldi cannot sent values in some form.
When submit some form, you can submit but without any value. This problem happens on Weblio English Japanese translation with sentence. http://ejje.weblio.jp/ Ameblo blog new post. http://ameblo.jp/ and more.
I reported this issue already (at 3 Feb 2015),
It is numbered VB-3036.
(Sorry, I had some mistake.)
But I didn't get e-mail about issue reports after this report,
and I got VB-3037's e-mail from Vivaldi Issue Tracker and E-Mail This Issue
but I got VB-3036's e-mail only from E-Mail This Issue. :huh: