Starting with today's update, BBEdit is a sandboxed app. This change had to make Bare Bones software, as BBEdit is to be included in the future in the Mac App Store.
Sandboxing on macOS restricts apps to intended use and is a protection that prevents malicious software from working. BBEdit requires explicit permission to access files and folders on the Mac.
However, to work properly, BBEdit often requires extended access to file and folder contents. A problem solving Bare Bones software with a request to enable sandbox access. This setting, says Bare Bones Software, will enable the full functionality of BBEdit without compromising security.
Without unrestricted access to your files and folders, many of the key features of BBEdit, from the most basic to the most powerful, will not work at all or they may misbehave in unexpected ways. At a minimum, this hampers your ability to do the work you do.
To resolve this fundamental conflict between security and usability, we've developed a solution in which BBEdit asks you to allow the same type of access to your files and folders that would be available to a non-sandboxed version.
For this reason, when you first launch BBEdit, you will be asked to allow this access. The request will not be repeated. However, if you do not allow this access and check it later, go to the application settings and click the Allow button in the Sandbox Access section.
Due to the changes, BBEdit can no longer access the support folder items in iCloud Drive, so those who have previously used iCloud Drive / Application Support / BBEdit will need to make some manual changes, such as in the Release notes for the update are described.
The new version of BBEdit also includes some enhancements to the app and a number of bugfixes that are also listed in the release notes.