# NetSurf/KolibriOS settings. Read once at startup from <exe dir>/res/settings.cfg.
# Format: key:value  (bool = 0/1). Lines starting with # are ignored.
# Any key can also be passed on the command line: netsurf --enable_js=1

# ---- content ----------------------------------------------------------

# JavaScript. Off by default: most pages render faster and more stably
# without it. The JS button in the toolbar toggles it per session.
enable_js:1

# Start page. Commented out means the built-in welcome page.
#homepage_url:

# Who the browser says it is, in the User-Agent header and in
# navigator.userAgent. One of: firefox (the default), chrome, android,
# netsurf, kolibrios -- or type a user agent string of your own and it is sent
# exactly as written. The honest "netsurf" one is not the default because
# search engines and CDNs answer it with a captcha or a scraper wall instead
# of a page. Try "android" if a site is heavy: the mobile version it serves is
# usually far smaller. "kolibrios" is the one WebView sends, and the only one
# that gets past the proof-of-work wall on kolibrios.org (which the browser
# already uses for that host on its own, whatever this is set to).
#user_agent:firefox

# Ad/tracker blocking, network half: third-party requests to the domains in
# res/adblock.dat are never sent, so the scripts never load.
js_adblock:1

# Ad blocking, cosmetic half: the UA stylesheet res/adblock.css hides ad
# furniture and collapses empty ad slots that would leave blank bands.
css_adblock:1

# Animated GIFs. Off saves a lot of redraws on busy pages.
animate_images:1

# <video>. 0 leaves the media alone -- not fetched, not decoded -- and the
# element still takes its place on the page, showing the poster image the
# author chose, or its own fallback content, or a placeholder. The escape
# hatch for a page whose video is not worth the megabytes on a slow link, and
# decoding one is the most expensive thing this browser does per second of
# wall clock.
enable_video:1

# Whether a video starts playing by itself once it has been decoded. This is
# the whole feature, not the page's autoplay attribute. There is no sound and
# no play button in the toolbar yet, so 0 currently means no video ever plays
# -- what it buys is that a page cannot take the machine over uninvited, which
# on a slow one it otherwise will.
video_autoplay:1

# Where downloaded files and "save link as" are written. The directory is
# created on demand. Default is the RAM disk, which is cleared on reboot.
download_path:/tmp0/1/Downloads

# ---- rendering --------------------------------------------------------

# Bilinear filtering of scaled images: nicer downscaled photos, slower plot.
# F1 toggles it at runtime.
img_smoothing:0

# SVG images (including inline <svg> icons). 0 draws a grey "SVG" plate
# instead of rasterising the vectors, which is the slowest image path here.
enable_svg:1

# WebP images. 0 draws a grey "WebP" plate instead of decoding.
enable_webp:1

# AVIF images. The most expensive decode here -- an AV1 intra frame, in C.
# 0 skips only the frame decode: boxes still lay out at the real size.
enable_avif:1

# Rounded corners (border-radius): the background, the frame around it, and
# the corners of a box that hides what overflows it.
# Off by default: the screen painter clips to rectangles, so a rounded box is
# drawn as one horizontal band per row of each corner arc instead of a single
# fill, and every box with a background pays a check to find out whether it is
# round at all. 0 draws the square corners earlier versions drew.
# The curves are antialiased, through the same vector rasteriser SVG uses.
# Box shadows stay square either way. A dotted or dashed frame keeps square
# corners too -- it is drawn as a patterned line, which cannot follow a curve.
enable_border_radius:0

# Page zoom, per cent. 100 = 1:1.
scale:100

# Dark theme preference. Also what pages see in prefers-color-scheme.
prefer_dark_mode:0

# CSS :hover. Off by default. When on, every pointer move over a page whose
# sheets use :hover re-selects the elements whose state changed: a rule that
# only recolours is applied in place and repainted, but one that moves
# anything falls back to a re-box, which on a large page is not free. Turn it
# on to get hover feedback, off if the pointer feels heavy.
enable_hover:1

# Lay the page out on demand while it is still parsing. NetSurf normally
# builds the box tree once, after the parse AND after every script has been
# fetched -- on airbnb.com that is ~2 minutes during which offsetWidth,
# offsetHeight and getBoundingClientRect all answer 0, because there is no
# layout to answer from. A React component that measures itself then latches
# that 0 for good: airbnb's "one price" dialog published it as
# `--text-height: 0px`, collapsed its own heading to 3px and dropped the
# button on top of the text.
#
# With this on, the first geometry read that finds no box lays the document
# out there and then -- once, and only when the body already has content and
# the parser is not on the stack. Everything after that is answered by real
# boxes. The cost is one extra conversion (1.2 s on airbnb, ~0.2 s on a small
# page) and a few re-boxes over the rest of the parse; a page that never
# measures pays nothing. Turn it off if a page loads worse than it renders.
provisional_layout:1

# ---- performance ------------------------------------------------------

# Fast mode: for an old machine. One switch that overrides the settings below
# it and in the rendering section -- SVG and AVIF images are not decoded (a
# grey plate is drawn at the right size instead), video is not fetched at all
# (the poster stays, so the page still reads), GIFs do not animate, scaled
# images are not smoothed, background images are neither fetched nor painted,
# CSS :hover does nothing, web fonts are not downloaded (the page is drawn in
# the built-in fonts), and the page is laid out once when the load finishes
# rather than again for every image that arrives. It also stops the
# two things that make the screen painter work pixel by pixel: a gradient
# becomes one flat fill in whichever colour covers most of the box, and a
# semi-transparent fill is rounded off -- a faint tint disappears, a heavy one
# is painted solid. Pictures keep their own transparency, so nothing grows
# black corners. Box shadows are not drawn: one of them is up to sixteen
# fills, and a page of cards has one on every card. It overrides those
# settings rather than changing them: turn
# it off and your own choices come back exactly as you left them, and this
# file is not rewritten behind you.
# Not included: JavaScript, which costs more than everything on this list put
# together on a modern page -- but is also the difference between a page and a
# blank screen. Turn enable_js off separately, or with the JS toolbar button,
# if you want that too.
fast_mode:0

# In-RAM cache of already fetched pages, images and stylesheets. Bigger means
# fewer refetches when going back or across pages of one site, at the cost of
# that much RAM. Either a size in MiB ("48") or a percentage of the RAM free at
# startup ("30%"). Clamped to 4..256 MiB either way.
memory_cache:30%

# On-disc cache, MiB. Survives restarts. Lives in cache/ next to netsurf.exe
# when that is writable, otherwise on the RAM disk (/tmp0/1/netsurf/cache) --
# where a large value is pointless, the whole disk is ~200 MiB.
disc_cache_mb:128

# Network timeout for one request, seconds.
curl_fetch_timeout:30

# Budget for ONE uninterrupted run of script -- one top-level script, one
# event handler, one callback -- before it is aborted, seconds. Not a budget
# for the page: the clock restarts every time the browser enters JS.
#
# This is a runaway-script guard, and on this machine the line between a
# runaway script and a big site is genuinely wide. browserscore.dev needs two
# runs of about 160 s (it runs a few thousand feature tests, then Vue builds
# ~35000 elements in one go); at 120 s both were cut off and the page came out
# white. The window is not frozen while a run goes on -- the loading page is
# laid out and repainted every 5 s, and the network keeps being pumped -- but
# nothing you type or click is looked at until the run ends, so this is also
# how long a bad page can ignore you. Lower it to 60 if that matters more than
# the heaviest sites rendering.
script_timeout:300

# ---- fonts ------------------------------------------------------------

# Web fonts: download the fonts a page asks for in its @font-face rules and
# draw its text in them, instead of in the fonts that ship with the browser.
# This is what makes a site look like itself, and it is the only way icon
# buttons -- the little symbols in toolbars and menus, which are delivered as
# a font, not as pictures -- come out right. It costs a download per font and
# a re-layout of the page when one arrives, so turn it off on a slow link and
# every page will still be readable in the built-in fonts. Fast mode turns it
# off for you.
enable_webfonts:1

# Render all glyphs 1-bit, no antialiasing. Fastest, ugliest.
fb_font_monochrome:0

# Subpixel (ClearType-style) antialiasing. Correct only on a real LCD;
# under a VM or over VNC it can fringe text with colour.
fb_font_subpixel:1

# Subpixel order of the panel: 0 = RGB, 1 = BGR. Only read when
# fb_font_subpixel is on.
fb_font_subpixel_bgr:0

# ---- diagnostics ------------------------------------------------------

# Debug log (logs/nsdbg.txt, beside netsurf.exe). 0 = off completely: the file
# is not even created and none of the per-line disk writes happen, which is
# worth a few per cent on a chatty page. F2 turns it back on mid-session.
# In autotest mode ("netsurf S <shot.png> <url>") the trace goes to
# <shot>.log instead, so a sweep keeps one log per URL; this key switches
# that off too.
enable_log:0

# Write the log a line at a time instead of in 32 KiB blocks. Off by default:
# every line becomes its own disk write and a busy page loads about a tenth
# slower. Turn it on when the browser is disappearing and you need the last
# lines before it went -- normally the crash handler flushes them for you, so
# this is only for a crash that takes the handler with it.
log_unbuffered:0

# Price each author-sheet rewrite by taking it out of its fused walk and
# timing the walk again (CSSRWPROF lines in nsdbg.txt). Only for sheets over
# 256 KB. Costs one extra walk per rewrite -- ibm.com takes about ten seconds
# longer to load with this on -- so leave it off unless you are reading the
# numbers.
css_rw_profile:0