I'm practically pulling my hair out on this!
When I select one line in a sketch as shown here I have the option to convert it to a construction line.
when I select 2 or more lines the option to change them all to construction lines disappears.
This just started yesterday. Normally I can select as many lines as I want to convert and do them all at the same time.
Oh look at that. I just answered my own question. Somehow I must have clicked the drop down arrow and hidden the option. it stays hidden until I click it down again.
I posted this because I was mostly done writing it when I figured out what was wrong. Maybe it can help someone else some day.
If you'll Ctrl+select multiple sketch entities and release Ctrl you should get these icons to choose from. So you can make them construction right there without needing to go to the Property Manager.
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