CRA does not natively support HTTPS on custom ports easily. Instead, use the HTTPS=true environment variable:
A standard SSL certificate is tied to a domain name (e.g., example.com ). localhost is a reserved, non-routable name. No global Certificate Authority (CA) can issue a publicly trusted certificate for localhost . Therefore, your development server generates a , which your browser distrusts by default.
Modern browsers (Chrome, Firefox, Edge, Safari) treat secure contexts as mandatory for powerful features:
If nothing is listening, start your intended service. https localhost 11501 url
: In your virtual host configuration file (e.g., /etc/apache2/sites-available/default-ssl.conf ), add or modify the following:
To help narrow down your specific issue with , please tell me:
What is your browser or terminal showing? CRA does not natively support HTTPS on custom ports easily
Developers frequently encounter specialized local URLs like https://localhost:11501 during local development, application testing, or when configuring self-hosted software. While it looks like a standard web address, this specific combination of a secure protocol (HTTPS), a local loopback address (localhost), and a designated port (11501) requires specific handling to function correctly.
Less commonly, a rogue process on your machine could open port 11501 to intercept traffic. However, if you recognize the application (e.g., a local Jupyter notebook, a GraphQL playground, or a testing UI), it is likely benign.
To the untrained eye, it’s just a web address. To a developer, it is a precise set of instructions. Here is the anatomy of https://localhost:11501 : No global Certificate Authority (CA) can issue a
const app = express();
When combined, the full address https://localhost:11501 instructs your browser to open a secure, encrypted connection to a web server running on your own computer, using port 11501 .
Browsers will usually show a certificate warning unless you’ve explicitly trusted a local CA for localhost .
mkcert -install
You’re trying to connect with HTTPS to a server that only speaks HTTP (or vice versa).
CRA does not natively support HTTPS on custom ports easily. Instead, use the HTTPS=true environment variable:
A standard SSL certificate is tied to a domain name (e.g., example.com ). localhost is a reserved, non-routable name. No global Certificate Authority (CA) can issue a publicly trusted certificate for localhost . Therefore, your development server generates a , which your browser distrusts by default.
Modern browsers (Chrome, Firefox, Edge, Safari) treat secure contexts as mandatory for powerful features:
If nothing is listening, start your intended service.
: In your virtual host configuration file (e.g., /etc/apache2/sites-available/default-ssl.conf ), add or modify the following:
To help narrow down your specific issue with , please tell me:
What is your browser or terminal showing?
Developers frequently encounter specialized local URLs like https://localhost:11501 during local development, application testing, or when configuring self-hosted software. While it looks like a standard web address, this specific combination of a secure protocol (HTTPS), a local loopback address (localhost), and a designated port (11501) requires specific handling to function correctly.
Less commonly, a rogue process on your machine could open port 11501 to intercept traffic. However, if you recognize the application (e.g., a local Jupyter notebook, a GraphQL playground, or a testing UI), it is likely benign.
To the untrained eye, it’s just a web address. To a developer, it is a precise set of instructions. Here is the anatomy of https://localhost:11501 :
const app = express();
When combined, the full address https://localhost:11501 instructs your browser to open a secure, encrypted connection to a web server running on your own computer, using port 11501 .
Browsers will usually show a certificate warning unless you’ve explicitly trusted a local CA for localhost .
mkcert -install
You’re trying to connect with HTTPS to a server that only speaks HTTP (or vice versa).
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