v1.8.21

Changelog

• 0fd5211 Merge pull request #225 from arran4/dependabot/golang-org-x-image-tiff-excessive-resource-consumption-3971930352942816695
• 902f064 Merge pull request #226 from arran4/fix-login-redirect-6656424172380060602
• f13ae04 Update golang.org/x/image to fix Dependabot alert
• fdc0045 feat: preserve current page and redirect back after login
• c9641a9 fix: address security feedback on open redirects