# Frequently asked questions

The Compiler
`<mail@qutebrowser.org>`

1. What is qutebrowser based on?

   qutebrowser uses Python, Qt and PyQt.

   The concept of it is largely inspired by dwb and Vimperator. Many actions and key bindings are similar to dwb.

2. Why another browser?

   It might be hard to believe, but I didn’t find any browser which I was happy with, so I started to write my own. Also, I needed a project to get into writing GUI applications with Python and Qt/PyQt.

   Read the next few questions to find out why I was unhappy with existing software.

3. What’s wrong with dwb/vimprobable/luakit/jumanji/… (projects based on WebKitGTK)?

   Most of them are based on the WebKitGTK+ WebKit1 API, which causes a lot of crashes. As the GTK API using WebKit1 is deprecated, these bugs are never going to be fixed.

   When qutebrowser was created, the newer WebKit2 API lacked basic features like proxy support, and almost no projects have started porting to WebKit2. In the meantime, this situation has improved a bit, but there are still only a few projects which have some kind of WebKit2 support (see the list of alternatives).

   qutebrowser uses Qt and QtWebEngine by default (and supports QtWebKit optionally). QtWebEngine is based on Google’s Chromium. With an up-to-date Qt, it has much more man-power behind it than WebKitGTK+ has, and thus supports more modern web features - it’s also arguably more secure.

4. What’s the difference to Firefox/Chromium addons like Tridactyl or Vimium?

   The WebExtensions API doesn’t seem to allow much freedom for plugin writers, which results in Vimium/Tridactyl not really having all the features you’d expect from a proper minimal, vim-like browser. Due to the same reason, those addons are quite inconsistent - on some pages, they can’t run and intercept keyboard inputs correctly. Tridactyl gets around those limitations with various measures (such as a native messenger written in Python doing some work which can’t be done from the addon directly), but there’s only so much that can be done.

5. Why Python?

   I enjoy writing Python since 2011, which made it one of the possible choices. I wanted to use Qt because of QtWebKit so I didn’t have many other choices. At that point, I wasn’t comfortable with C++ so that wasn’t an alternative.

6. But isn’t Python too slow for a browser?

   It’s generally less of a problem than one would expect. Most of the heavy lifting of qutebrowser is done by Qt and QtWebKit/QtWebEngine in C++, with the GIL released.

   It can be problematic in some areas, but various performance optimizations have been carried out to problematic portions of the code.

7. Is qutebrowser secure?

   Most security issues are in the backend (which handles networking, rendering, JavaScript, etc.) and not qutebrowser itself.

   qutebrowser uses QtWebEngine by default. QtWebEngine is based on Google’s Chromium. While Qt only updates to a new Chromium release on every minor Qt release (all ~6 months), every patch release backports security fixes from newer Chromium versions. In other words: As long as you’re using an up-to-date Qt, you should be receiving security updates on a regular basis, without qutebrowser having to do anything. Chromium’s process isolation and sandboxing features are also enabled as a second line of defense.

   QtWebKit is also supported as an alternative backend, but hasn’t seen new releases in a while. It also doesn’t have any process isolation or sandboxing. See #4039 for more details.

   Security issues in qutebrowser’s code happen very rarely (as per September 2019, there have been three security issues caused by qutebrowser in almost 6 years). Those were handled appropriately (example) and fixed timely. To report security bugs, please contact me directly at mail@qutebrowser.org, GPG ID 0x916eb0c8fd55a072.

8. Is there an ad blocker?

   Since version 2.0.0, if the Python `adblock` library is available, it will be used to integrate Brave’s Rust adblocker library for improved adblocking, based on ABP-like filter lists (such as EasyList). If that library is unavailable or on older versions of qutebrowser, a simpler built-in ad blocker is used instead. It takes `/etc/hosts`-like lists and thus is only able to block entire hosts.

   Note that even the more sophisticated blocker does not support element hiding (cosmetic filtering) yet, it only blocks network requests.

9. How can I get No-Script-like behavior?

   To disable JavaScript by default:

       :set content.javascript.enabled false

   The basic keybinding for enabling JavaScript for the current host is `tsh`. This will allow JavaScript execution for the current session. Use `S` instead of `s` to make the exception permanent. With `H` instead of `h`, subdomains are included. With `u` instead of `h`, JavaScript is allowed for the current URL only (not the whole host).

   The list of domains that have been permanently granted permission to execute JavaScript will be written to `autoconfig.yml`.

10. How do I play Youtube videos with mpv?

    You can easily add a key binding to play youtube videos inside a real video player - optionally even with hinting for links:

        :bind ,m spawn mpv {url}
        :bind ,M hint links spawn mpv {hint-url}

    The comma prefix is used to make sure user-defined bindings don’t conflict with the built-in ones.

    Note that you might need an additional package (e.g. youtube-dl on Archlinux) to play web videos with mpv.

    There is a very useful script for mpv, which emulates "unique application" functionality. This way you can add links to the mpv playlist instead of playing them all at once.

    You can find the script here: https://github.com/mpv-player/mpv/blob/master/TOOLS/umpv

    It also works nicely with rapid hints:

        :bind ,m spawn umpv {url}
        :bind ,M hint links spawn umpv {hint-url}
        :bind ;M hint --rapid links spawn umpv {hint-url}

11. How do I use qutebrowser with mutt/neomutt or other mail clients?

    For security reasons, local files without `.html` extensions aren’t rendered as HTML, see this Chromium issue for details. You can do this in your `mailcap` file to get a proper extension:

        text/html; qutebrowser %s; needsterminal; nametemplate=%s.html

    Note that you might want to add additional options to qutebrowser, so that it runs as a separate instance configured to disable JavaScript and avoid network requests, in order to avoid privacy leaks when reading mails. The easiest way to do so is by specifying a non-existent proxy server, e.g.:

        qutebrowser --temp-basedir -s content.proxy http://localhost:666 -s content.dns_prefetch false -s content.javascript.enabled false %s

    With Qt 6, using something like:

        qutebrowser --temp-basedir -s content.dns_prefetch false -s content.javascript.enabled false %s

    should lead to a similar result, due to a more restrictive implementation of the `content.local_content_can_access_remote_urls` setting (`false` by default already). However, it’s advised to use a page like Email Privacy Tester to verify your configuration.

12. What is the difference between bookmarks and quickmarks?

    Bookmarks will always use the title of the website as their name, but with quickmarks you can set your own title.

    For example, if you bookmark multiple food recipe websites and use `:open`, you have to type the title or address of the website.

    When using quickmark, you can give them all names, like `foodrecipes1`, `foodrecipes2` and so on. When you type `:open foodrecipes`, you will see a list of all the food recipe sites, without having to remember the exact website title or address.

13. How do I use spell checking?

    Configuring spell checking in qutebrowser depends on the backend in use (see #700 for a more detailed discussion).

    For QtWebKit:

    1. Install qtwebkit-plugins.

    2. Note: with QtWebKit reloaded you may experience some issues. See #10.

    3. The dictionary to use is taken from the `DICTIONARY` environment variable. The default is `en_US`. For example to use Dutch spell check set `DICTIONARY` to `nl_NL`; you can’t use multiple dictionaries or change them at runtime at the moment. (also see the README file for `qtwebkit-plugins`).

    4. Remember to install the hunspell dictionaries if you don’t have them already (most distros should have packages for this).

       For QtWebEngine:

    5. Use `dictcli.py` script to install dictionaries. Run the script with `-h` for the parameter description.

    6. Set `spellcheck.languages` to the desired list of languages, e.g.: `:set spellcheck.languages "['en-US', 'pl-PL']"`

14. How do I use Tor with qutebrowser?

    Start tor on your machine, and do `:set content.proxy socks://localhost:9050/` in qutebrowser. Note this won’t give you the same amount of fingerprinting protection that the Tor Browser does, but it’s useful to be able to access `.onion` sites.

15. Why does J move to the next (right) tab, and K to the previous (left) one?

    One reason is because dwb did it that way, and qutebrowser’s keybindings are designed to be compatible with dwb’s. The rationale behind it is that J is "down" in vim, and K is "up", which corresponds nicely to "next"/"previous". It also makes much more sense with vertical tabs (e.g. `:set tabs.position left`). If you prefer swapped bindings, you can run `:bind J tab-prev` and `:bind K tab-next` to swap them.

16. What’s the difference between insert and passthrough mode?

    They are quite similar, but insert mode has some bindings (like `Ctrl-e` to open an editor) while passthrough mode only has shift+escape bound. This is because shift+escape is unlikely to be a useful binding to be passed to a webpage. However, any other keys may be assigned to leaving passthrough mode instead of shift+escape should this be desired.

17. Why does it take longer to open a URL in qutebrowser than in chromium?

    When opening a URL in an existing instance, the normal qutebrowser Python script is started and a few PyQt libraries need to be loaded until it is detected that there is an instance running to which the URL is then passed. This takes some time. One workaround is to use this script and place it in your $PATH with the name "qutebrowser". This script passes the URL via a unix socket to qutebrowser (if its running already) using socat which is much faster and starts a new qutebrowser if it is not running already.

18. How do I make qutebrowser use greasemonkey scripts?

    There is currently no UI elements to handle managing greasemonkey scripts. All management of what scripts are installed or disabled is done in the filesystem by you. qutebrowser reads all files that have an extension of `.js` from the `<data>/greasemonkey/` folder and attempts to load them. Where `<data>` is the qutebrowser data directory shown in the `Paths` section of the page displayed by `:version`. If you want to disable a script just rename it, for example, to have `.disabled` on the end, after the `.js` extension. To reload scripts from that directory run the command `:greasemonkey-reload`.

    Troubleshooting: to check that your script is being loaded when `:greasemonkey-reload` runs you can start qutebrowser with the arguments `--debug --logfilter greasemonkey,js` and check the messages on the program’s standard output for errors parsing or loading your script. You may also see javascript errors if your script is expecting an environment that we fail to provide.

    Note that there are some missing features which you may run into:

    1. Some scripts expect `GM_xmlhttpRequest` to ignore Cross Origin Resource Sharing restrictions, this is currently not supported, so scripts making requests to third party sites will often fail to function correctly.

    2. Any greasemonkey API function to do with adding UI elements is not currently supported. That means context menu extentensions and background pages.

19. How do I change the `WM_CLASS` used by qutebrowser windows?

    Qt only supports setting `WM_CLASS` globally, which you can do by starting with `--qt-arg name foo`. Note that all windows are part of the same qutebrowser instance (unless you use `--temp-basedir` or `--basedir`), so they all will share the same `WM_CLASS`.

20. How do I use X.509 Client Certificates?

    Right now there is no certificate-chooser prompt implemented when there are multiple matches. Subscribe to Issue#4587 for progress notifications.

    QtWebEngine will attempt to use certificates stored in `${HOME}/.pki/nssdb`. If you have Chromium installed, you can import the certificate there and qutebrowser will pick it up as well. Alternatively, you can use the `certutil` commandline tool:

    Assuming you have a CA Certificate and a Client Certificate that you want for authenticating yourself on a web service that validates against this CA Certificate, you need to perform the following steps.

    1. Import the CA Certificate

           certutil -d "sql:${HOME}/.pki/nssdb" -A -i <path_to_ca_cert.pem> -n "My Fancy CA" -t "TC,C,T"

    2. Merge your `<cert.crt>` and `<privkey.pem>` files into a single `PKCS#12` certificate file (optional, skip if your Client Certificate already is in `PKCS#12` format)

           openssl pkcs12 -export -in <path_to_client_cert.crt> -inkey <path_to_client_cert_privkey.pem> -out my_fancy_client_cert.pkcs12

    3. Import your Client Certificate into the certificate store

           pk12util -d "sql:${HOME}/.pki/nssdb" -i <path_to_my_fancy_client_cert.pkcs12> -n "My Fancy Client Certificate"

       Upon visiting a website that requests a Client Certificate you should now be prompted by qutebrowser whether you want to submit the newly imported Client Certificate or not.

       If you ever need to renew any of these certificates, you can take a look at the currently imported certificates using:

           certutil -d "sql:${HOME}/.pki/nssdb" -L

       Then remove the expired certificates using:

           certutil -d "sql:${HOME}/.pki/nssdb" -D -n "My Fancy Certificate Nickname"

       And then import the new and valid certificates using the procedure described above.

21. Is there a dark mode? How can I filter websites to be darker?

    There is a total of four possible approaches to get dark websites:

    - The `colors.webpage.preferred_color_scheme` setting tells websites that you prefer a light or dark theme. However, this requires websites to ship an appropriate dark style sheet. The setting requires a restart and QtWebEngine with at least Qt 5.14.

    - The `colors.webpage.darkmode.*` settings enable the dark mode of the underlying Chromium. Those setting require a restart and QtWebEngine with at least Qt 5.14. It’s unfortunately not possible (due to limitations in Chromium and/or QtWebEngine) to change them dynamically or to specify a list of excluded websites. There is some remaining hope to allow for this using HTML/CSS features, but so far nobody has been able to get things to work (even with Chromium) - help welcome!

    - The `content.user_stylesheets` setting allows specifying a custom CSS such as Solarized Everything. Despite the name, the repository also offers themes other than just Solarized. This approach often yields worse results compared to the above ones, but it’s possible to toggle it dynamically using a binding like `:bind ,d config-cycle content.user_stylesheets ~/path/to/solarized-everything-css/css/gruvbox/gruvbox-all-sites.css ""`

    - Finally, qutebrowser’s Greasemonkey support should allow for running a stripped down version of the Dark Reader extension. This is mostly untested, though.

22. How do I make copy to clipboard buttons work?

    You can `:set content.javascript.clipboard access` to allow this globally (not recommended!), or `:set -u some.domain content.javascript.clipboard access` if you want to limit the setting to `some.domain`.

## Troubleshooting

Unable to view Flash content.

  If you have Flash installed for on your system, it’s necessary to enable plugins to use the flash plugin. Using the command `:set content.plugins true` in qutebrowser will enable plugins. Packages for Flash should be provided for your platform or it can be obtained from Adobe. Note that QtWebEngine needs PPAPI Flash, while QtWebKit needs NPAPI Flash.

Unable to view DRM content (Netflix, Spotify, etc.).

  On Arch Linux, simply install `chromium-widevine` from the AUR.

  For other distributions, it should be possible to obtain the needed widevine files and store them in the correct places, but the details differ wildly between various Qt versions.

Unable to use `spawn` on MacOS.

  When running qutebrowser from the prebuilt binary (`qutebrowser.app`) it will not read any files that would alter your `$PATH` (e.g. `.profile`, `.bashrc`, etc). This is not a bug, just that `.profile` is not propagated to GUI applications in MacOS.

  See Issue #4273 for details and potential workarounds.

QtWebKit: Experiencing freezing on sites like DuckDuckGo and YouTube.

  This issue could be caused by stale plugin files installed by `mozplugger` if mozplugger was subsequently removed. Try exiting qutebrowser and removing `~/.mozilla/plugins/mozplugger*.so`. See Issue #357 for more details.

My issue is not listed.

  If you experience any segfaults or crashes, you can report the issue in the issue tracker or using the `:report` command. If you are reporting a segfault, make sure you read the guide on how to report them with all needed information.

## GitHub Sponsors FAQ

Using GitHub Sponsors, you can sign up for a monthly donation to The-Compiler (qutebrowser’s main developer), allowing him to work part-time on qutebrowser. If you keep your donation level for long enough, you can get some qutebrowser stickers!

Why GitHub Sponsors?

  GitHub Sponsors is a crowdfundign platform nicely integrated with qutebrowser’s existing GitHub page and a better offering than alternatives such as Patreon or Liberapay.

  It also offers a Matching Fund which matches all donations until a cap of $5000, which has already been reached by qutebrowser.

Is it possible to contribute via a one-time donation instead?

  Yes! GitHub Sponsors allows for one-time donations (including custom amounts) using the buttons next to "Select a tier". Alternatively, see the readme for other donation methods, but note that physical rewards (stickers/shirts) for such donations are handled on a case-by-case basis due to the higher administrative overhead and fees.

I’d like a certain reward (e.g. a t-shirt) but I’d prefer making a smaller monthly donation. Can I upgrade via a one-time donation?

  GitHub allows for one-time donations (see the previous question). For physical rewards, your total contributions will be summed up, so you can indeed make a one-time donation to "upgrade". Before rewards are ordered, all sponsors will be contacted with their total donation amount so that they can still upgrade, if desired.

GitHub tries to charge me for an entire year. What gives?

  This happens if you have an existing annual billing cycle with GitHub (for example a Pro membership or Marketplace subscription). At the moment, GitHub’s billing system only supports annual sponsor payments in that case.

Can I support you without getting any rewards/merchandise?

  Absolutely! Any merchandise is optional. Before sending out merchandise I’ll distribute forms asking for size/address/etc. - those forms will have an option to not get any merch at all.

Can I select my own amount rather than using the predefined tiers?

  At the bottom of the tier list, GitHub allows specifying a custom donation amount.

When will rewards be shipped?

  Due to COVID-19, the Swiss Post currently only accepts priority letters for many countries, including the US. Especially for the t-shirts, the difference between economy and priority shipments is quite significant. For the shirts, I estimate I’d spend a total of $250 to $1500 on extra postage. Thus, shipping is currently on hold until the shipping situation resolves. There’s currently no ETA for that happening, but rest assured everyone will be notified (if contact details are available) once there are news.

I’d like some stickers, but I can’t donate anything because of my financial situation.

  Please get in touch! As long as this doesn’t get abused, I’d happily send stickers for free.

We’re a company interested in sponsoring qutebrowser, can you invoice us for the sponsored amount?

  You will receive a confirmation mail including a PDF receipt from GitHub when sponsoring qutebrowser. If you really need an invoice, I can bill you via my company, Bruhin Software. Please get in touch to discuss details!

Can you share details on the stickers?

  There are two sticker designs: Rectangular stickers (with text) and round vinyl stickers. Those are the same as during the 2016/2017 crowdfundings.

Can you share details on the swag?

  A limited number of metal buttons and magnets is available:

  It’s planned to order more swag, depending on the exact demand. Possibilities would include:

  - qutebrowser pens (refillable)

  - notebooks (the paper kind)

  - USB-sticks (for the "expensive swag" reward).

Can you share details on the t-shirts?

  The shirts will be B&C #E190 shirts which are the successor to the "Exact 190" shirts distributed in the previous crowdfundings: 100% cotton and relatively thick/heavy.

  Sizes from XS and 5XL are available, most of them also as a fitted (women) cut. Up to 40 colors are available from the supplier - there will be a selection of recommended/tested colors, but any available color can be selected on your own risk.

  The print will be a white silk-screen print, with the same design as in the 2016 crowdfunding:

## Privacy Policy

Being a mostly volunteer-run project, qutebrowser does not have the resources for a full legalese version of a privacy policy. Instead, this overview should answer the most common questions.

For any privacy questions, please contact privacy@qutebrowser.org.

### Website

The qutebrowser.org website does not use any cookies or trackers. It does not store any logs, except in rare situations when those are explicitly (and temporarily) enabled to debug website issues. Even if enabled, IP addresses are partially redacted in the logs. As soon as debugging is finished, any logs are removed.

Note that some services related to qutebrowser are stored on third-party services such as GitHub. By using their websites, you’re subject to their privacy policies.

### Crash reports

When qutebrowser crashes or you use the `:report` command, you have the possibility to send a crash report. If you decide to do so, your crash report is stored on qutebrowser’s server, where qutebrowser’s maintainer (Florian Bruhin / The Compiler) can access it. Before February 2021, other core qutebrowser developers (a maximum of four people total) could access the reports as well (access was restricted based on the sensitive nature of those reports, not because of any known issues with those individuals).

If you select the option to include a debug log with your report, it’s possible that sensitive information is contained in your report. You can show and edit the log in the crash report window to redact any such information as you see fit. Additionally, qutebrowser tries to avoid logging information such as passwords entirely (by not logging any input going to websites).

Currently, crash reports are stored indefinitely for technical reasons. With a new tool designed for crash reports, it’ll become possible to delete crashreports after the underlying issue is fixed, but that tool needs some more work before qutebrowser can use it.

### Application

Without any user interaction, qutebrowser can be expected to make no unsolicited requests. It does not contain any telemetry code.

The QtWebEngine library (on which qutebrowser is based on) strips out any Chromium features which talk to Google servers, so any unsolicited requests should be treated as a bug.

While qutebrowser uses DuckDuckGo as the default search page, no advertising deal exists between DuckDuckGo and qutebrowser. Note that by visiting DuckDuckGo, you’re subject to their privacy policy.

With regard to websites you visit, qutebrowser tries to strike a balance between usability/compatibility and privacy. There are various `content.*` settings which can be used to tweak such behavior, reduce fingerprinting or disable various features (usually at a cost of website compatibility).