Any reason why it doesn't automatically choose the entire chain?
It's hard to remember how things worked in 2014.
Maybe because these are construction entities? Convert to normal, try the offset, then convert them back to construction??
Another thing is to do a repair on the software. This is a good idea anyways to do from time to time when the software gets "buggy".
I am still running SW2014.
It appears to be associated with construction geometry. Without launching the offset command, instead RMC on your sketch chain that is NOT construction geometry and you should see "Select Chain" in the menu. Now repeat for the construction geometry chain - the "Select Chain" option is missing. Convert the construction geometry to regular geometry and repeat. The "Select Chain" option will now appear in the menu.
Interesting catch. I had never noticed this behavior until you pointed it out.
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