Add support for Firefox in a Snap for Ubuntu 22.04

Closes #327
Fixes #325

truststore_darwin.go

@@ -16,7 +16,7 @@ import (
 )
 
 var (
-	FirefoxProfile      = os.Getenv("HOME") + "/Library/Application Support/Firefox/Profiles/*"
+	FirefoxProfiles     = []string{os.Getenv("HOME") + "/Library/Application Support/Firefox/Profiles/*"}
 	CertutilInstallHelp = "brew install nss"
 	NSSBrowsers         = "Firefox"
 )

truststore_linux.go

@@ -15,8 +15,9 @@ import (
 )
 
 var (
-	FirefoxProfile = os.Getenv("HOME") + "/.mozilla/firefox/*"
-	NSSBrowsers    = "Firefox and/or Chrome/Chromium"
+	FirefoxProfiles = []string{os.Getenv("HOME") + "/.mozilla/firefox/*",
+		os.Getenv("HOME") + "/snap/firefox/common/.mozilla/firefox/*"}
+	NSSBrowsers = "Firefox and/or Chrome/Chromium"
 
 	SystemTrustFilename string
 	SystemTrustCommand  []string

truststore_nss.go

@@ -27,6 +27,7 @@ var (
 		"/usr/bin/firefox",
 		"/usr/bin/firefox-nightly",
 		"/usr/bin/firefox-developer-edition",
+		"/snap/firefox",
 		"/Applications/Firefox.app",
 		"/Applications/FirefoxDeveloperEdition.app",
 		"/Applications/Firefox Developer Edition.app",
@@ -128,8 +129,12 @@ func execCertutil(cmd *exec.Cmd) ([]byte, error) {
 }
 
 func (m *mkcert) forEachNSSProfile(f func(profile string)) (found int) {
-	profiles, _ := filepath.Glob(FirefoxProfile)
+	var profiles []string
 	profiles = append(profiles, nssDBs...)
+	for _, ff := range FirefoxProfiles {
+		pp, _ := filepath.Glob(ff)
+		profiles = append(profiles, pp...)
+	}
 	for _, profile := range profiles {
 		if stat, err := os.Stat(profile); err != nil || !stat.IsDir() {
 			continue

truststore_windows.go

@@ -17,7 +17,7 @@ import (
 )
 
 var (
-	FirefoxProfile      = os.Getenv("USERPROFILE") + "\\AppData\\Roaming\\Mozilla\\Firefox\\Profiles"
+	FirefoxProfiles     = []string{os.Getenv("USERPROFILE") + "\\AppData\\Roaming\\Mozilla\\Firefox\\Profiles"}
 	CertutilInstallHelp = "" // certutil unsupported on Windows
 	NSSBrowsers         = "Firefox"
 )