Oof, yeah that looks horrendous in Arctic.
Arctic does have support for spoilers, though currently some elements are not hidden by the spoiler tag such as thematic breaks (horizontal lines) code-blocks etc. I’ll need to fix that. Table support is planned, though I haven’t figured out a good way to accomplish this yet.
I’ll do some testing over the weekend and see if I can at least get some rudimentary tables working so that content like this is readable while I come up with a more refined solution.
Thanks for letting me know!