For security, at least store passwords hashed with salt and validate and escape all user inputs. Consider scanning for top vulnerabilities on the top of OWASP list, and use a canary token. None of which impacts usability.
For usability, I'd consider accessibility basics, such as minimum color contrast, minimum button size, etc.
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For security, at least store passwords hashed with salt and validate and escape all user inputs. Consider scanning for top vulnerabilities on the top of OWASP list, and use a canary token. None of which impacts usability.
For usability, I'd consider accessibility basics, such as minimum color contrast, minimum button size, etc.