This document outlines the common configuration options supported by the NetSurf core.

Overview

The users configurations are generally stored in a "Choices" file and are loaded at browser startup. Most user interfaces provide a way to configure these parameters in a manner consistant with the toolkit in use.

The user choices are stored as a simple key:value list.

Each entry has a type, one of: boolean, integer, unsigned integer, hexadecimal colour value or string.

General Options

Option Key	Type	Default	Description
http_proxy	bool	false	An HTTP proxy should be used.
http_proxy	bool	false	An HTTP proxy should be used.
http_proxy_host	string	NULL	Hostname of proxy.
http_proxy_port	int	8080	Proxy port.
http_proxy_auth	int	0	Proxy authentication method.
http_proxy_auth_user	string	NULL	Proxy authentication user name
http_proxy_auth_pass	string	NULL	Proxy authentication password
http_proxy_noproxy	string	localhost	Proxy omission list
font_size	int	128	Default font size / 0.1pt.
font_min_size	int	85	Minimum font size.
font_sans	string	NULL	Default sans serif font
font_serif	string	NULL	Default serif font
font_mono	string	NULL	Default monospace font
font_cursive	string	NULL	Default cursive font
font_fantasy	string	NULL	Default fantasy font
accept_language	string	NULL	Accept-Language header.
accept_charset	string	NULL	Accept-Charset header.
memory_cache_size	int	12MiB	Preferred maximum size of memory cache in bytes.
disc_cache_size	uint	1GiB	Preferred expiry size of disc cache in bytes.
disc_cache_age	int	28	Preferred expiry age of disc cache in days.
disc_cache_path	string	NULL	Path to disc cache, NULL means to use system path
block_advertisements	bool	false	Whether to block advertisements
do_not_track	bool	false	Disable website tracking [1]
send_referer	bool	true	Whether to send the referer HTTP header.
foreground_images	bool	true	Whether to fetch foreground images
background_images	bool	true	Whether to fetch background images
animate_images	bool	true	Whether to animate images
enable_javascript	bool	false	Whether to execute javascript
script_timeout	int	10	Maximum time to wait for a script to run in seconds
expire_url	int	28	How many days to retain URL data for.
font_default	int	0	Default font family
ca_bundle	string	NULL	ca-bundle location
ca_path	string	NULL	ca-path location
cookie_file	string	NULL	Cookie file location
cookie_jar	string	NULL	Cookie jar location
homepage_url	string	NULL	Home page location
search_url_bar	bool	false	search web from url bar
search_provider	int	0	default web search provider
url_suggestion	bool	true	URL completion in url bar
window_x	int	0	default x position of new windows
window_y	int	0	default y position of new windows
window_width	int	0	default width of new windows
window_height	int	0	default height of new windows
window_screen_width	int	0	width of screen when above options were saved
window_screen_height	int	0	height of screen when above options were saved
toolbar_status_size	int	6667	default size of status bar vs. h scroll bar
scale	int	100	default window scale
incremental_reflow	bool	true	Whether to reflow web pages while objects are fetching
min_reflow_period	uint	25	Minimum time (in cs) between HTML reflows while objects are fetching
core_select_menu	bool	false	Use core selection menu

[1] http://www.w3.org/Submission/2011/SUBM-web-tracking-protection-20110224/#dnt-uas

Fetcher options

Option Key	Type	Default	Description
max_fetchers	int	24	Maximum simultaneous active fetchers
max_fetchers_per_host	int	5	Maximum simultaneous active fetchers per host. (<=option_max_fetchers else it makes no sense) [2]
max_cached_fetch_handles	int	6	Maximum number of inactive fetchers cached. The total number of handles netsurf will therefore have open is this plus option_max_fetchers.
suppress_curl_debug	bool	true	Suppress debug output from cURL.
target_blank	bool	true	Whether to allow target="_blank"
button_2_tab	bool	true	Whether second mouse button opens in new tab.

[2] Note that rfc2616 section 8.1.4 says that there should be no more than two keepalive connections per host. None of the main browsers follow this as it slows page fetches down considerably. See https://bugzilla.mozilla.org/show_bug.cgi?id=423377#c4

PDF / Print options

Option Key	Type	Deflt	Description
margin_top	int	10	top margin of exported page
margin_bottom	int	10	bottom margin of exported page
margin_left	int	10	left margin of exported page
margin_right	int	10	right margin of exported page
export_scale	int	70	scale of exported content
suppress_images	bool	false	suppressing images in printed content
remove_backgrounds	bool	false	turning off all backgrounds for printed content
enable_loosening	bool	true	turning on content loosening for printed content
enable_PDF_compression	bool	true	compression of PDF documents
enable_PDF_password	bool	false	setting a password and encoding PDF documents

System colours

These are the css system colours which the browser also uses to style generated output.

Option Key	Type	Default
sys_colour_ActiveBorder	colour	0x00d3d3d3
sys_colour_ActiveCaption	colour	0x00f1f1f1
sys_colour_AppWorkspace	colour	0x00f1f1f1
sys_colour_Background	colour	0x006e6e6e
sys_colour_ButtonFace	colour	0x00f9f9f9
sys_colour_ButtonHighlight	colour	0x00ffffff
sys_colour_ButtonShadow	colour	0x00aeaeae
sys_colour_ButtonText	colour	0x004c4c4c
sys_colour_CaptionText	colour	0x004c4c4c
sys_colour_GrayText	colour	0x00505050
sys_colour_Highlight	colour	0x00c00800
sys_colour_HighlightText	colour	0x00ffffff
sys_colour_InactiveBorder	colour	0x00f1f1f1
sys_colour_InactiveCaption	colour	0x00e6e6e6
sys_colour_InactiveCaptionText	colour	0x00a6a6a6
sys_colour_InfoBackground	colour	0x008fdfef
sys_colour_InfoText	colour	0x00000000
sys_colour_Menu	colour	0x00f1f1f1
sys_colour_MenuText	colour	0x004e4e4e
sys_colour_Scrollbar	colour	0x00cccccc
sys_colour_ThreeDDarkShadow	colour	0x00aeaeae
sys_colour_ThreeDFace	colour	0x00f9f9f9
sys_colour_ThreeDHighlight	colour	0x00ffffff
sys_colour_ThreeDLightShadow	colour	0x00ffffff
sys_colour_ThreeDShadow	colour	0x00d5d5d5
sys_colour_Window	colour	0x00f1f1f1
sys_colour_WindowFrame	colour	0x004e4e4e
sys_colour_WindowText	colour	0x00000000