It works for me.
You have to be in modify tab, edge sub-object level

(
	max modify mode
	subobjectlevel = 2
	
	f1=8
	f2=6
	
	$.modifiers[#Edit_Poly].BridgeEdges f1 f2 node:$
	$.modifiers[#Edit_Poly].Commit ()
)

If you can bridge f1 and f2(the same edge indexes) manually, then the script can do it too.

Thank you, miauu! Your script worked great. I used it to create a screw thread. The client needs to see the wear on the thread so I couldn鈥檛 collapse the helix > bevel profile it to an epoly.

Here鈥檚 what I did:

Create Helix > set properties > add bevel profile modifier
Create shape for bevel profile (in my case it was a square with one side missing)

| <鈥搇ike that!
/

Apply shape as profile
Add EditPoly modifier to helix
get the edge numbers of the first two adjacent edges (manually)

then execute this script

	f1=2 //the number of the bottom edge
	f2=2264 //the number of the top edge
	
	ne = $.edges.count/4 //4 is the number of sides of your bevel shape
for x = 1 to ne do
(
	max modify mode
	subobjectlevel = 2
	
	$.modifiers[#Edit_Poly].BridgeEdges f1 f2 node:$
	$.modifiers[#Edit_Poly].Commit ()
	
	f1+=3 //you may have to adjust this depending on what your profile looks like.
	f2 +=2 //you may have to adjust this depending on what your profile looks like.
)

Put the max modify mode and subobjectlevel = 2 outside of the for loop.
Yo have to go to modify panel and edge sub-object level only once, so no need to do this on ivery iterration in the loop.

f1=2 //the number of the bottom edge
	f2=2264 //the number of the top edge
	
	ne = $.edges.count/4 //4 is the number of sides of your bevel shape
max modify mode
subobjectlevel = 2
for x = 1 to ne do
(	
	$.modifiers[#Edit_Poly].BridgeEdges f1 f2 node:$
	$.modifiers[#Edit_Poly].Commit ()
	
	f1+=3 //you may have to adjust this depending on what your profile looks like.
	f2 +=2 //you may have to adjust this depending on what your profile looks like.
)

do you know what:

you can do 鈥渂ridge鈥?without Edit Poly modifier

so you can do it

being not in the modifier panel

with not selected editable poly

and being not in the edge sub-selection mode

which will allow you do it

much faster

with no any viewport or UI flickering

I can do that to a spline with only a bevel profile modifier added to it?

what you are doing is a tool鈥?the using of some modifiers is just a pipeline. there is no difference to keep modifiers on stack or collapse them all.