https://proton.me/support/sieve-advanced-custom-filters
good luck
i think you would want to start with:
if header :matches "from" "somedomain" { discard; }
but i am just spitballing.
EDIT: i think there is a "reject" as well.
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https://proton.me/support/sieve-advanced-custom-filters
good luck
i think you would want to start with:
if header :matches "from" "somedomain" { discard; }
but i am just spitballing.
EDIT: i think there is a "reject" as well.
This is the basic filter. No idea about sieve filters.
Using a browser
Left side scroll down to "labels" and hit the cog.
Again on the left hit "filters".
Add filter, name the filter, hit next.
You can select subject, sender and 2 other options, add something to the box (perhaps the email you found in the header), hit next,
Now, decide where you want the email to go.