On the day after Halloween, a manila envelope was waiting for us in our mailbox.

‘To the owners of this house’ was scrawled on the front with cursive text that reminded me of my grandmother’s handwriting.

Who had I irked this time? Was a reader upset about something I’d written for Dutch News? Had I cut ahead of someone in the checkout line at Albert Heijn or failed to wipe down the handles on a treadmill at the gym?

Instead of contacting the authorities, I discussed the situation with my partner and finally opted to open the envelope in our garden to be on the safe side. It had just been Halloween after all.

Every October, we fill our front windows with Halloween decorations. We put up holographic paintings similar to the ones at Phantom Manor at Disneyland Paris, a life-sized raven, a cheeky Beetlejuice poster, and lots of fake cobwebs.

The display, which is more humorous than horrifying, attracts a fair amount of attention. I actually keep a tally of the number of fascinated kids and begrudging parents who visit our ghoulish gallery.

International students who may have never encountered a Halloween display even sometimes stop to take photos. One girl was out there for ten minutes last week snapping selfies and photographing every single detail.

But there’s also more than a few older Dutch people who stop to sneer and shake their heads.

The envelope wasn’t stuffed full of arsenic, nor was it a ‘glitter bomb.’ Instead, it contained a lovingly crafted painting of a paper lantern alongside song lyrics. Written on the opposite side was a melancholy note from the artist lamenting the fading traditions of Sint-Maarten.

Sint-Maarten is the Netherlands’ more traditional “candy holiday” and it falls on November 11. Children typically go from door to door with colourful lanterns on sticks and sing songs from years gone by in exchange for sweets.

But how can a comparatively tame and gentle festivity like Sint-Maarten possibly hold up against a holiday that encourages kids to dress up as everyone from the KPop Demon Hunters to Cristiano Ronaldo and get candy without having to sing for it?

Paper lanterns and old-timey tunes can’t quite compete with the modern fun of 21st century Halloween.

We’re not sure what to do with the Sint-Maarten painting given to us by the mysterious artist. There’s also the question of their intentions.

Was this a passive-aggressive move to convince us to decorate for Sint-Maarten? Is it even possible to decorate for Sint-Maarten? And would doing so give them the impression they’ve won a minor victory in the ongoing clash between these two holidays?

We discussed the painting with a few friends, one of whom theorised the culprit is a retired art teacher with nothing better to do than pester people with editorialised paintings. Another suggested we hang it in one of the windows with a Sint-Maarten lantern and see if they show up on the night of November 11.

At the time of this writing, we haven’t made a decision, but there is another option we’re mulling over since we haven’t taken down the display yet.

We might stick little Santa hats on all of our Halloween ghosts and ghouls and keep them in the windows well past New Year.