FWIW, any time I'm in a situation where I might have this happen, I add blue dye to the mix to be absolutely sure where it's been sprayed. So it my very extensive use of herbicides for the past 20 years, I've never had 'glyphosate footprints'. I do very occasionally have other 'intended consequences' but experience teaches one how to avoid those.
For example I just sprayed the English Ivy in a dead tree. Now without going into the 'politics' of invasives, I get why people in the US see it as a problem; but in certain areas of my garden, I just don't see it as nearly as much of a problem as various other things. I'm fine with it being a ground cover in semi-wild areas, because, if not ivy, something like poison ivy will just take over that space. So there are areas where I let it lie on the ground. THAT BEING SAID, I now stop it climbing things, and I will not allow it to flower anywhere on my property, ever. This tree had been covered for years, but never flowered...this year it started, and would have made lots of seeds! (Around here they take years and years to flower, even once they've climbed a tree) I have found before that merely ringing the trunk to cut the stems is not enough. In our climate, at least, the ivy seems able to suck moisture either out of the air, or the dead trunk, and stay alive for years. Can 100% guarantee you I've observed this. So in addition to doing that, I sprayed as much of the foliage as I could with Crossbow. A very powerful herbicide...similar probably not available in EU/UK except to licensed applicators. I had a variegated Pittosporum that was potentially in the drip area, which I covered with an upturned dustbin. (see, I've translated for the forum LOL) No sense in taking any chances even though I probably could have avoided spraying it.
Between the stems being cut and being sprayed w/crossbow, I hope to at least arrest the production of seeds, even though it might take one more application to fully kill it. We'll see. Glyphosate can kill ivy, but it takes extra long, even by the standards of glyphosate, and I worried it would manage to still mature the seeds. BTW while I've gone into this, I deliberately did it Thursday when we were having the first winds of the approaching storm, but no forecast of rain, to keep the crossbow ester vapours moving. You never want to spray a lot of that on a still day, because even without direct contact, the fumes can damage stuff. (though probably not kill - again no sense taking chances)
English isn't really a general weed here, but if you happen to have it in your yard , it's a pain like everywhere else, I gather. I've got a patch that came with the house, and it'll be going holus-bolus at some point, but it'll have to be blackberry killer or glyphosate when the time comes. I've always had a soft spot for things that survive the summer half of the year with no water at all, and ivy is one of those plants, but it's so rampant lt has to go. Same thing with bloody morning glory - I planted a piece voluntarily and now it races across the yard like a triffid and gets into everything, so I'm finally killing it off with glyphosate.