[Using 3.4.10 on Windows 10; Refer to the attached photos.]
Despite having a global ignore file set (Sourcetree2.jpg) that contains a list of file types to ignore (Sourcetree3.jpg), SourceTree still displays those files under "Unstaged files" (Sourcetree1.jpg). Um, that is the whole point of an ignore is to -- well, ignore the files.
Indeed, SourceTree recognizes they are ignored because it won't let me re-ignore them; i.e., the Ignore option is disabled (Sourcetree4.jpg) when I right-click on one of the files.