From 1986: the launch issue of JEM, published by London Editions.
This was, of course, another toy-animation-merchandising triple play by the guys at Hasbro. The enjoyable animated series (from the Hasbro-Sunbow-Marvel alliance) was a fixture of the TV-am weekend schedules for a while. The premise was to spice up the traditional Barbie market with a range of highly fashionable dolls based around the concept of an all girl rock group.
LE quietly cut a niche for themselves by being the 'other' publisher of such licensed fare, although they seldom gave Marvel UK much to worry about. Their biggest hit was MASTERS OF THE UNIVERSE (a property the British Bullpen let slip through their fingers) but they also published SHE-RA, MY LITTLE PONY (writing for that must have been painful... and just how does a pink horse play tennis anyway?), BATTLE BEASTS (originally, in Japan at least, part of the TRANSFORMERS universe), CENTURIONS and no doubt others I didn't notice or have long forgotten.
Most LE titles suffered from sub-standard - and usually uncredited - artwork which I always had the suspicion originated somewhere in Europe. Although I'm not sure if that is actually true or not.
Jem has subsequently returned to comics in a new series from IDW. There was also a underwhelming feature film reboot which managed to be a lot worse than the JOSIE AND THE PUSSYCATS film of a generation ago, not least because they tried to bolt on a silly high-tech subplot (a nod to the original I think) onto what should have been a fairly decent flick about a teen who becomes a rock star in the age of social media. I'm still flummoxed by the fact that no one recognised her, despite apparently living an average teenage life. The now obligatory end of movie teaser, which introduced rival rockers the Misfits, promised a far more interesting follow-up, which won't happen thanks to a disastrous worldwide box office gross.
I've no idea how long the British Jem comic stayed in the charts. This is the only issue I've ever seen.