Sometimes I miss fair and critical voices in this forum.
Almost everyone here seems to justify any behaviour of DW.
For me it very clearly a deficiency, when a file manager of an app does not overtake the behaviour of the standard file manager of the OS. Here we talk about hidden files.
(Reposted from previous thread)
If it isn't intended to be managed or transferred by Dreamweaver, it really shouldn't be in the site folder. Dreamweaver shouldn't be expected to execute OS-level management, and that would be potentially problematic were it introduced into features. I could only imagine how many countless unintended document "hidings" would cause unending file and GIT/repository errors, not to mention misleading team devs. You would be safer setting expectations and standards/convention at your team level to get your file managers to safely move the files out of the site as part of their process.