Improve the UX when users can't access to http://proxy.man/ssl

[NghiaTranUIT]

Problem

Some users can't download the Proxyman Certificate from proxy.man/ssl to their remote device. Therefore, they thought that Proxyman server is down.

proxy.man/ssl is not a real URL. It's only available if the HTTP proxy setting is correct.

Current Solution

• They have to follow step-by-step this troubleshooting to diagnose what problem is.
• Maybe HTTP Proxy IP/Port is wrong, or VPN or Firewall Setting, ....

Solution

• Rename proxy.man/ssl to cert.proxyman.io
• cert.proxyman.io is a real website -> Show the explanation and help them to fix the problem

Why this feature/change is important?

• Users don't need to ask us every time they can't access proxy.man/ssl
• They are aware of what is wrong and fix it.

[NghiaTranUIT]

Update for macOS / Windows /Linux

• For the UI: Replace proxy.man/ssl -> cert.proxyman.io
• For the code: Don't remove proxy.man/ssl. It's important to support compatible with old URLs.
• Add new URL: cert.proxyman.io to download the current certificate
• Verify the user can download the certificate with both URL on iPhone, or Firefox
• Try to set wrong IP or Port in the Proxy Setting in iPhone -> Access cert.proxyman.io -> Verify I can see the real website -> Follow the troubleshooting on website -> Fix the IP / Port -> I can download the certificate again.

[NghiaTranUIT]

Done: https://download.proxyman.io/beta/Proxyman_5.4.0_New_cert.proxyman.io.dmg