The last time I checked, it was not possible to write a Chrome Extension for TiddlyWiki that works in the same way as TiddlyFox. Chrome restricts extensions to a sandboxed portion of the file system; they don’t have access, for example, to your Dropbox folder. So, the extension would require any TiddlyWiki’s to be imported into the sandbox before they can be saved. Because the sandbox is private to the extension, the extension would have to be responsible for syncing content to the cloud to get it on other devices. I believe that TiddlyChrome is subject to these restrictions.
Given Google’s biases, the way to get the best from TiddlyWiki on Chrome is to use it over http:// instead of file://, either by using a cloud hosted provider like TiddlySpot, or a local Node.js instance. Google continue to progressively restrict operations from file:// URLs. From their perspective, the capability is a security risk; the only thing stopping Google from disabling file:// URIs altogether is the outcry from web developers. But there is no doubt in my mind that that is the way that they are going. For Google, security is the overriding concern.
That’s why Firefox is adopting the same approach to security, and banning old-school extensions that have unrestricted access to the browser innards. It’s not viable for Mozilla to knowingly be less secure than the market leading browser, and so it’s pretty much guaranteed that they will continue to follow Google down the path of (a) restricting operations from file:// URLs and (b) severely limiting the powers of browser extensions.
Luckily, there are several different ways of using TiddlyWiki:
(1) As a local file with the HTML5 compliant “download” saver (that’s the one that re-downloads the HTML file each time it is saved). Even though the user experience is lumpy, and puts quite a lot of pressure on the user, this approach is simple and reliable, and I’ve been surprised to learn that many people use it as their everyday method of using TiddlyWiki
(2) As a local file with the Firefox-specific TiddlyFox extension
(3) As a local file with a Chrome-style restricted extension (eg TiddlyChrome)
(4) Via a locally run server
(5) Via a remote, cloud-based server
For the moment, we only need to worry about (2) going away; all the other ways of saving are not threatened.
One final point, as I’ve said before, I do not think that making the single file edition easier to use is the best way to get TiddlyWiki more widely used. Working with the single file edition is inherently conceptually alien and risky for anyone raised on conventional, contemporary web services; the barriers are not just about the number of clicks. I believe that the way to get TiddlyWiki more widely used is through online implementations that avoid the user having to worry about saving.
Best wishes
Jeremy