No need to use Chrome. If you have Radian, you can even use the Eclipse Map in the field without an internet connection. Here is how:
The 2017_eclipse.map project uses imageserver layers that were created with persistent caching turned off. You can replace those with imageserver layers with caching turned on, and then load them up when you are connected to Internet.
1. Launch the .map at a time when your computer has Internet access.
2. Open the Map and delete the imageserver background layers.
3. Delete the imageserver datasources that are in the project.
4. Create whatever imageserver data sources you like, for example, Bing streets and Bing satellite. The default setting when you create an image server is that it saves a cache of every tile you downloaded in the project.
6. Out in the field, you won't need to zoom into the entire US. You just need the region around your viewing site. Zoom into the map in that site and pan and zoom around the way you would on your way there. Zoom into the region where you expect to zoom and move the viewport around to view the area in reasonably high zoom level near the viewing site. Doing that loads the cache in the project with all the tiles from the image server that display those views.
7. Save the project. It could be very big from the large size of the cache, easily a few hundred MB. What do you care? You might have a 10 GB movie on the same drive to view on the flight to the site. :-)
The next time you open that saved project all those tiles in the cache will still be there. If you pan and zoom in the project the image servers will still appear to work, at least if you stay within the limits of what you browsed when you were connected to Internet.
Manifold has been my "go to" application in the field for catching eclipses. When weather is poor and you have to find a break in the clouds at the very last second using Manifold can make the difference between a clear view of totality (a truly awesome event) and just standing around under an overcast sky while it gets dark. No comparison.
One more tip: if the weather forecast looks dicey, with cloud cover but not total overcast, that is, with breaks in the clouds that move over the landscape, it helps to have a strategy to move around fast in the last few moments. The best is to find a highway or road that aligns with the eclipse centerline. You can then position yourself on the shoulder of the road and be ready to zoom off chasing a break in the clouds right up to the moment of totality.
That strategy worked very well for the 1999 total eclipse in Germany. Our group was one of the few that saw totality on what turned out to be a rainy day. We found a length of a few tens of kilometers on the autobahn between Munich and Salzburg that aligned with the center line path of totality and arrived early at the Western end of the route we expected we might have to take.
Every half-minute or so right up to totality we'd hop in the cars and all zoom off down the autobahn skipping along to try to get in the path of one of the clear spots between heavy clouds just before the start of totality. We used Manifold with the GPS tracker and atomic clock time from the GPS to synchronize exactly to the start of totality. Our last launch further East was just sixteen seconds before totality.
Moments before totality we jumped out of the cars to look upwards just as a clear spot began passing overhead. We had a superb view of totality. Just as the sun re-emerged a heavy rain began to fall as the clouds moved in. Super! ...and would have been impossible without something like Manifold in use in real time.
Most people in Germany just saw dark clouds that got a lot darker for about two minutes. We saw that eternal, incredible hole open up in the sky, like a portal to another dimension.
By the way, the government is going overboard scaring people into wearing the equivalent of welder's googles for eye protection. Wear welder's goggles during totality and you won't see anything. The key is to not look at the Sun until totality starts, but once totality starts (obvious) you can look directly at the eclipse with perfect safety. The moment the Sun comes out you should look away, but for all of totality it's perfectly safe to look directly at the eclipse.
If you want to keep track of what the eclipse is doing until totality, pick any piece of stiff paper and put a pinhole in it so you can make a camera obscura projection onto the ground and see the crescent shape of the disappearing Sun. Heck, you can even make a small opening between fingers by overlapping your hands held flat that will give the same effect.