Thank you so much, this is a great question and a classic example of networking and how I discover stuff for my blog post. In fact it will be a blog post and I am also copying another LI connect because I was talking to her earlier about a similar issue- your question led me to something I don’t think either of us knew.
To answer your question, I did some testing on a testing profile I have set up. And first I will say that I didn’t have a clue you could even write something I thought you had to pick from the LI provided list. So you knew something I didn’t. I went to the section where you enter skills and sure enough you can make up your own professions. I think 70 characters is about the max. What I found is, whatever you write, it has to fit on one line. If it takes more than one line it didn’t work for me. So if you keep it to around 70 characters I think you are good. I also found I could delete one if it was too long and not lose the rest. I saved after I added one.
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