Ok, so as I was writing the question I think I stumbled on the fix. In my installed fonts (Start/Run/Fonts), I somehow had Helvetica Black, but not any other version of Helvetica. It seems Chrome was picking the black version making everything look super bold. I certainly didn't manually install Helvetica Black on two computers in the last week, but it's possible that Chrome recently changed how it picks fonts or I used/installed some other software that installed Helvetica Black?
To recap, my fix was:
- Go to your fonts folder (Start/Run/Fonts)
- Find and delete Helvetica Black
The Office "Online" applications are basically crapware. They are "light" versions of the full install applications. They are adequate for creating simple documents and viewing or doing simple edits of documents created on full versions of the application. They are missing most features. Specifically, they do not allow you to change font substitution nor font embedding.
So, basically, you have to work on the file in a full install of Word, rather than Word Online.
In the full version you have 2 options. You can embed your custom font, if your purchase of the font gave you the right to do that (have to check if you can embed the font and if it is embedded can it be used to edit the document. Those are separate rights that have to be granted.)
Or in the full version you can define the specific font substitution you want Windows to use. Pick a font that is commonly installed on most Windows versions so you know it will work.
Fonts that are installed with Microsoft Office 2013
MS Typography, Fonts by product or family
If you don't get full answers in time, you can go to Microsoft Community, a user support forum sponsored by MS.
It has over a dozen sub forums for various MS products such as Office and Windows.
If you have bug reports, or want to submit a request for a new feature, the place to go is the "UserVoice" forum. MS has set up a bunch of subsites there. Real MS Staffers read all of the postings, and they even act on a few of them. Follow this link for a collection of MS UserVoice subsites.
Best Answer
If you want to use Helvetica, you will have to buy it.
Helvetica is a licensed font family, any company wishing to use it must pay to do so. Windows has free-to-use alternatives such as Arial and Calibri but Helvetica is not freely available.
You can buy Windows TTF format fonts which will work with all applications, but anything you give to someone else will likely fall back to using Arial.