* lisp/progmodes/project.el (project-find-file-in):
Bind completion-ignore-case to the value of
read-file-name-completion-ignore-case (bug#41902).
(defun project-find-file-in (filename dirs project)
"Complete FILENAME in DIRS in PROJECT and visit the result."
(let* ((all-files (project-files project dirs))
+ (completion-ignore-case read-file-name-completion-ignore-case)
(file (funcall project-read-file-name-function
"Find file" all-files nil nil
filename)))