I have seen several posts on people asking you about Chromebook support and am disappointed at your lack of support for this OS. For those of us that run our businesses off of Chromebooks it is a disappointment to say the least. I am required to remember (aka word or google doc) all passwords and usernames and then when I get home put them into my personal desktop windows machine 1Password app because when I work out of my home I use a Chromebook. Using the excuse of "we are unsure about the future of Chromebooks because they may merge with Android" is poor and honestly not accurate since Google itself has said they will continue to support Chrome OS after any Android and Chrome merger - http://www.theverge.com/2015/10/30/9641952/google-chrome-os-not-dead-hiroshi-lockheimer . You already have a fully functioning Chrome extension. The only limitation is that you require a local dropbox account, this is the disconnect for Chromebooks. (Your app is the only reason I even use dropbox anymore as I have moved everything to Google Drive.) If you added an online function for dropbox like you do in your android app (since the dropbox android app cannot store dropbox files locally you already know how to implement this feature) or added support for Google Drive (something that anyone on Chrome or with a Chromebook will already have) then you will have access to your .js file in the cloud at all times. No local sync needed. There are several apps that already use this feature in the chrome store to sync content across Chrome browsers on all platforms so this is not a new concept.
Please create something viable for your users across all major platforms. It is clear that you have many users begging for this feature.
I will give you a few more months in hope that a chrome extension will emerge since I have already paid for your product on a few different platforms but if this is not added soon I will be moving to LastPass. I don't like the idea of the subscription-based service of LastPass (which is why I chose you to begin with) but at least it works on all modern operating systems. At least they are up to date with current technology trends.