For the past couple months now, my comrade has been searching desperately for a TV commercial for cereal that she claims aired in 1987. She says the commersh included a free bubble gum offer, but she doesn't remember what brand of cereal or bubble gum.
The main thing she remembers about the commersh is that it showed a youngster blowing a bubble in slow motion - accompanied by electronic tones that sounded like the old PBS bumper of the '70s and '80s.
YouTube searches have proven fruitless.
I thought I remembered there being a pack of Bubble Yum inside boxes of Cheerios, but I can't say for sure.
However, I think Flickr might be a better bet at finding it. Try looking through this album (https://flic.kr/s/aHsiN9iMSU) as a starting point, and maybe some of the cross-referenced cereal-related albums as well.
Scroll down a little at https://www.mrbreakfast.com/cereal_detail.asp?id=165
Unable to find a commercial for that particular giveaway however...
Bing turned up some images of a lot of different cereals that included gum giveaways. Don't know whether any of this might help:
https://www.bing.com/images/search?q=cereal+bubble+gum+giveaway&qpvt=cereal+bubble+gum+guveaway&FORM=IQFRML&PC=APPL
I remember the "monster cereals" having a Super Bubble offer, and having a funny drawing on the back of the box showing Count Chocula, Franken Berry, and Boo Berry blowing bubbles. This was around 1983.