Proxies
Enable seamless configuration of the browser’s proxy settings by using a PAC (Proxy Auto-Config) script or any of the other supported methods.
A PAC script is a small JavaScript file that tells the browser how to route each web request—deciding whether to send it directly or through one or more proxy servers. By defining these rules in a single, centralized file, you can:
-
Send different URLs through different proxies.
-
Bypass the proxy when connecting to local or trusted hosts.
-
List multiple proxies in order of preference, with a final fallback to direct connection.
You can also configure proxies by setting environment variables, using system properties, integrating with your desktop’s system proxy settings, or leveraging WPAD (Web Proxy Auto-Discovery).
PAC Script (Proxy Auto-Config)
Equo Chromium provides system property to configure proxies by pointing to a PAC script. A PAC script uses a standard JavaScript function, FindProxyForURL(url, host)
, which returns a proxy configuration string for each request. Equo Chromium can fetch and evaluate this script at startup.
Environment Variables
Equo Chromium honors the standard UNIX environment variables for proxies:
export http_proxy="http://proxy-user:proxy-pass@proxy.example.com:3128"
export https_proxy="http://proxy-user:proxy-pass@proxy.example.com:3128"
export ftp_proxy="http://proxy.example.com:3128"
export no_proxy="localhost,127.0.0.1,*.mycompany.internal"
-
http_proxy
/https_proxy
/ftp_proxy
: Full proxy URLs including credentials. -
no_proxy
: Comma-separated hostnames/domains to bypass the proxy. Wildcards supported.
Chromium Proxy Flags via System Property
Chromium proxy flags must be passed via the -Dchromium.args
system property. Multiple flags must be semicolon-separated in a single quoted string.
-
Force all traffic through a proxy:
-Dchromium.args="--proxy-server=http://proxy.example.com:3128"
-
Use a PAC script:
-Dchromium.args="--proxy-pac-url=http://proxy.example.com/config.pac"
-
Add a proxy bypass list:
-Dchromium.args="--proxy-server=http://proxy.example.com:3128;--proxy-bypass-list=localhost;127.0.0.1;*.internal"
-
Enable WPAD:
-Dchromium.args="--proxy-auto-detect"
System Proxy Settings (Desktop Integration)
Equo Chromium integrates with your desktop environment’s proxy settings.
-
GNOME:
GSettings
keys read at startup (e.g.,/system/proxy/mode
,/system/proxy/autoconfig-url
) -
KDE: Settings read from
KConfig
or environment variables (e.g.,HTTP_PROXY
) -
XFCE and others: Proxy picked up from exported environment variables
WPAD (Web Proxy Auto-Discovery)
Chromium supports automatic discovery of a PAC script via WPAD:
-
Automatically queries DHCP (Option 252) or DNS (
wpad.<domain>/wpad.dat
) -
Can also be explicitly enabled:
-Dchromium.args="--proxy-auto-detect"
Chromium Preferences File (Advanced/Static Configuration)
You can define proxy settings in Chromium’s JSON preferences file:
-
Edit
~/.config/chromium/Default/Preferences
and add:{ "proxy": { "mode": "fixed_servers", "server": "socks5://127.0.0.1:1080", "bypass_list": ["localhost", "127.0.0.1", "*.internal"] } }
Supported modes:
* pac_script
(requires pac_url
)
* fixed_servers
* system
* auto_detect
Summary of Available Methods
-
-Dchromium.proxy_pac_script
— Load PAC script via system property -
Environment variables —
http_proxy
,https_proxy
,no_proxy
-
Supported Chromium flags passing them via
-Dchromium.args
. -
System proxy settings — GNOME, KDE, XFCE integration
-
WPAD — DHCP/DNS-based PAC script discovery
-
Preferences file — Static JSON configuration for locked-down setups