Nor did the stable version
I'm sorry, but Vivaldi is not supported at the moment and there is no plan for doing that in the near future either.
It doesn't work because Vivaldi is not implementing properly/completely Chrome's extensions API (and I suspect it has a lot of bugs too; I just found a couple in the first 5 minutes after I installed it). Opera, on the other hand, has no problems and Window Resizer seems to work just fine on it so you might want to give it a try.
Could this issue be resolved in any way ?
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