Google Chrome is deprecating Java NPAPI Support
From Bravenet Wiki
Google has plans to deprecate NPAPI support from the Google Chrome browser. NPAPI is what allows Java and similar plugins to operate on the browser. This means that Bravenet customers using Google Chrome may need to use a different browser, or third-party File Transfer Protocol, to make use of certain Bravenet features that require Java to work on the browser.
You can find more information from Google on the NPAPI plugin support here:
Information directly from Java about Chrome NPAPI support:
What it affects
The Bravenet SFTP Applet, used to upload/download small files from the browser, requires Java support in the browser to operate. The SFTP Applet won't run on Chrome 42 and higher that have NPAPI support disabled.
What can be done
First and foremost, we suggest reactivating NPAPI support on your Google Chrome browser if possible, or you may need to install and use a different browser. Mozilla Firefox is recommended in this area.
Alternatively, you can make any necessary FTP uploads/downloads that would otherwise require the SFTP Applet, using a third-party FTP client on your computer itself. For example, WinSCP is a free third-party File Transfer Protocol client, that is available for download and use from the provider website for free, and straightforward to use.
What we suggest
Third-party, free FTP programs such as WinSCP are designed for secure, effective file transmission in mind, and so your best bet for a consistent and reliable experience with updating your website would be to setup an FTP client on your workstation/computer.
To that end, we advise customers use WinSCP for upload/download instead of the Java SFTP Applet, if necessary.