Can't make the popup appear in a web game

[syt0r]

I'm trying to use yomitan in a web-page game Granblue Fantasy (https://game.granbluefantasy.jp/)

The game has unselectable text everywhere which I can turn off by disabling 2 user-select properties, then I can copy all text there and use google look up from context menu, but hovering cursor over selected text with shift button pressed doesn't make popup appear and launching yomitan from context menu when selecting text isn't very consistent and not that comfortable, is there any other trick I can use to make it work?

[syt0r]

It's weird, it seems like this is the website among several I've tested that doesn't print anything in console when I try to add event listener like this

document.addEventListener("keydown", (event) => {
    console.log(event.key, event);
});

It's probably somehow preventing yomitan from detecting clicks on the shift button, as well as any other buttons