yay --diffmenu using kompare opens empty

[nihakuto]

Affected Version

yay v12.3.5 - libalpm v14.0.0

Describe the bug

When using yay to compile/install AUR software, if the user opts to view diffs, the configured diff tool kompare is opened but without the files preselected, resulting in a kompare window with empty fields.

Reproduction Steps

1. Configure kompare as the diff tool for yay (via git's config, the $GIT_PAGER or $PAGER environment variables).
2. Use yay to update an AUR package.
3. When prompted to view diffs, select "Yes".
4. Observe that kompare opens but without preselecting the diff files/PKGBUILD.

Expected behavior

kompare should open with the diff files preselected, showing the differences between the files.

Output

$ yay -Pg
{
	"aururl": "https://aur.archlinux.org",
	"aurrpcurl": "https://aur.archlinux.org/rpc?",
	"buildDir": "/home/dois/.cache/yay",
	"editor": "",
	"editorflags": "",
	"makepkgbin": "makepkg",
	"makepkgconf": "",
	"pacmanbin": "pacman",
	"pacmanconf": "/etc/pacman.conf",
	"redownload": "no",
	"answerclean": "",
	"answerdiff": "",
	"answeredit": "",
	"answerupgrade": "",
	"gitbin": "git",
	"gpgbin": "gpg",
	"gpgflags": "",
	"mflags": "",
	"sortby": "votes",
	"searchby": "name-desc",
	"gitflags": "",
	"removemake": "ask",
	"sudobin": "sudo",
	"sudoflags": "",
	"version": "12.3.5",
	"requestsplitn": 150,
	"completionrefreshtime": 7,
	"maxconcurrentdownloads": 5,
	"bottomup": true,
	"sudoloop": false,
	"timeupdate": false,
	"devel": false,
	"cleanAfter": false,
	"keepSrc": false,
	"provides": true,
	"pgpfetch": true,
	"cleanmenu": true,
	"diffmenu": true,
	"editmenu": true,
	"combinedupgrade": false,
	"useask": false,
	"batchinstall": false,
	"singlelineresults": false,
	"separatesources": true,
	"debug": false,
	"rpc": true,
	"doubleconfirm": true,
	"rebuild": "no"
}