Add .dropboxignore directory to exclude folders without using selective sync

Dropbox should learn git and provide ignore configuration files, including global ignore and specific directory ignore. I am using Free File Sync software. This software will create temporary files while scanning directories that need to be synchronized. At the same time, many other programs frequently create or delete very small temporary files. I tried the ignore command provided by Dropbox, something like "Set-Content -Path 'C:\Users\xxx\Dropbox\xxx' -Stream com.dropbox.ignored -Value 1". But it seems that the above command only works for long-lived files. Although the file names of temporary files do not change, they are always deleted and recreated frequently. Even if the command can be modified to also work on temporary files, the command is still inconvenient. Creating a plain text ignore file is obviously more user-friendly than operating complex commands.
So I suggest that Dropbox add ignore file support as soon as possible.