People discover little-known Christmas light hack – and it's left many gobsmacked

Christmas is creeping up around the corner...

Although the majority of people across the UK will have completed their festive decoration, some might leave it to the very last minute. Others, however, will have finished it all but are looking for ways to jazz it up once the whole family are round.

Now over on TikTok, one user has gone viral after revealing they were "today years old" when finding out what the red lights are for. User @viznelly, who scooped over 4,800 fans in the past few years, revealed they "didn't know" the light bulbs had a secret function.

In the video, they said: "I was today years old when I found out what these are for. Remove regular bulb and replace." Then moments later, the person added: "Wait for it," while zooming out to show the red bulb blinking and flashing among the white lights.

Not only does the trick give it that little Christmas feel, it means you can have the flashy function, or replace a broken bulb ahead of the big day. Bulbs can often break, especially if you're reusing lights from the previous year.

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But with this hack, it means you don't have to spend a fortune on a new set. At the time the video was shared, it scooped 1.8million likes and nearly 6,800 comments. And it's safe to say the comments are rather divided.

One said: "I'm still confused, why is it still red?" While another added: "The blinky lights are nice but having one red bulb would bother me." A third commented: "I still don't get it."

But fortunately, some people were clearly aware of how handy the hack would be during the Christmas period. Someone said: "Wait what? I thought they were replacements." As another chimed in: "I clearly know nothing."

And a third added: "I thought they were replacement bulbs if one burnt out, lol." Then a TikTok user pointed out: "Who didn't know this lol." And a second posted: "Are 90s kids shocked y'all didn't know this."

In case you're still confused, replacing one of your Christmas tree light bulbs with a red-tipped bulb makes the circuit flash and blink, according to Christmas Light Source. They can also work as replacements which could help you save money.