Taking care of what you already have often just means catching the small stuff before it turns into the big stuff. This time it was a hairline crack in the old tiled stove — easy to seal now, a lot more work to deal with if I’d left it.
A bit of heat-resistant filler, worked carefully into the gap and smoothed level with the tile. Not glamorous work, but it’s the kind of maintenance that keeps an old feature like this both functional and good-looking for another few decades.
Same philosophy as the garden, really: notice the small problems early, and most things last far longer than you’d expect.