A man on The You Tube drilled his frame but measured his frame for the hole to be away from the weld zone.
The obvious place for my frame is opposite a direct mount front mech.
Obviously this is welded on . Is this an issue? I’ve never heard anyone else mention weld zones when drilling for a dropper.

its outside the Heat Affected Zone if its on the other side of the weld
so should be as good a place as any, but Id like to know more about this

I wouldn’t want it close to a structural weld but opposite a derailleur mount like that wouldn’t bother me.

I’ve done a few, with no ensuing fiery death. Stay away by about 20mm from the weld areas – that might narrow your choice a bit.
I’d actually say 180 degrees from the front mech mount might not be great (this is based on uneducated experience drilling holes in unstayed dinghy masts, so YMMV – basically, you’ll have a potential weak point on both sides of a tube). I’d drill on the front left side of the seat tube looking at that pic, if it were my bike.
That said, pretty much every mtb these days has holes drilled all over the shop, albeit often with reinforcing pockets brazed or welded in. Remove stress risers and smooth edges and you should be good.

I was looking g at Liteville instructions for drilling a dropper , and they say to drill a hole which just drills into the weld approx 2 mm
It was and 8mm hole they suggested

Bentudder, did I buy a scandal off you?
Your dropper hole was perfect!

A picture of the other side, if that helps.

I’d put it on the front, centrally between the two decals purely because it would look the neatest.