Known issues in the current version
The Pale Moon browser, at any point in time, may have a number of known
issues. These known issues will usually be addressed in the next
release of the browser, or it may be something that people have noticed
and are mentioned here because they are "by design", i.e.: issues
people have asked about, are known, and are this way on purpose.
For each issue, check the status for intended action to be taken in
development (if any) and intended timeline (if applicable).
Known issues in 24.1.2:
rendering of text and graphics may become "pixelated"
If you are using Windows 7 SP1 with the recently (Feb 28th
2013) released Windows Platform Update (KB 2670838), or
potentially also if you are using Windows 8, and your system is
equipped with an ATI/AMD Radeon HD3000 or HD4000 series graphics
processor, you may encounter issues with rendering text and graphics in
page content, similar to:
This is caused by the combination of OS, the Platform Update which
makes changes to DirectX acceleration, and the graphics
hardware/drivers in your system. Microsoft is still triaging this
issue. Note that it may be installed as a prerequisite for using MSIE
Workaround: See http://forum.palemoon.org/viewtopic.php?f=1&t=2228
- TL;DR: uninstall KB2670838
Status: [In Progress] - Mozilla is working on workarounds in code but they cause performance regressions.
Known issues in the 3.6.*
versions (Legacy, discontinued):
Known issues in all versions:
sites render particularly slow or stall the browser, or don't display
This is caused by the websites in question using more modern website
coding, notably more advanced HTML5 and CSS3, that is not and will not
be supported by the Legacy version of Pale Moon (the Gecko rendering
engine used in this version does not properly support it).
Solution: Upgrade to
the Next Generation version of Pale Moon
(if your hardware and O.S. support it).
Status: [Inherent, won't fix]
browser creates directories under %APPDATA%\Mozilla, specifically
These directories are related to the underlying Mozilla extension code (Pale Moon is a Mozilla-based browser)
and stores extension IDs there. This issue is completely harmless and
non-breaking; in fact, having (all) Mozilla-based applications use this
one central location for extension IDs is desired.
Status: [By Design]
Known issues in previous versions
Because issues in previous versions may still apply to what people are
running, here is a recap of previous, still recent versions that have been fixed, and potential workarounds:
- If using the menu drop-down list to list tabs, the top entry appears twice
If you choose to display existing tabs as a list instead of the default
pane with thumbnails, the first tab (top entry) will appear twice in
the list. This is related to the removal of Tab Groups that previously
masked an underlying Firefox bug.
Timeline: Fixed in 24.1.0
- In certain situations, the
text may become unreadable
This happens in the following combination of
- You are using Windows Glass (Aero)
- You are not using a theme/persona
- You are using an inverted color scheme for Windows (e.g. high
- You visit a broken/mixed-mode secure site
This is caused by the new theming for broken secure sites not taking
this particular combination of circumstances into account, causing
light text on a light address bar background.
Several possibilities to work around the problem:
- Either: use a dark persona/theme - this will remove the light address bar
- Disable URL bar shading in preferences (in about:config, set browser.padlock.urlbar_background to 0), OR
- Add the following code to your userChrome.css file:
background-color: rgb(12,0,0) !important;
Timeline: Fixed in 24.0.1
- Themes don't apply to private browsing windows
This is caused by the switch to the new Gecko code base and the
relevant script not being subsequently patched (module location changed
in the source tree).
Workaround: Download the replacement script module here, and unzip it into your Pale Moon installation folder under "modules", replacing the existing copy of LightweightThemeConsumer.jsm. Completely close and restart the browser for the change to come into effect.
Timeline: Fixed in 24.0.1
- Disk cache size has an incorrect default
The disk cache size is changed to 1GB (the old maximum) upon first
start of the browser if it was previously not set by the user.
This should remain the (default) value of 250MB of cache
Workaround: in Options -> Advanced -> Network, set the cache size to 250MB
Timeline: Fixed in 24.0.1
- On some systems, viewing images can cause UI problems
On some systems, viewing an image as a standalone file in the browser
and switching tabs/minimizing the browser may cause UI rendering issues
(blank address bar, system controls or tab headers, missing icons) or
potentially excessive CPU usage. The cause of this is related
to the address bar and tab header icon (favicon) generated from the image.
Workaround: in about:config, set browser.chrome.image_icons.max_size to the value 0 (zero). This will disable the generation of thumbnails for images.
Timeline: Fixed in 24.0.2
extensions will not work in Pale Moon
Pale Moon may not support the latest versions of
"Add-On SDK" (formerly Jetpack) extensions. This is caused by several
Workaround: Install an older version of the add-on
- The extension in question may not ship the Add-On SDK
its installation. The SDK and loader was moved to the Firefox core,
meaning it was no longer necessary for add-on developers to include the
SDK in their add-on packages. If the SDK is not otherwise installed on
your system, the add-on won't work (compare this with a .NET
application requiring the .NET framework being installed on your system)
- Some versions of the Add-on SDK have a too strict check
on browser engines, which will result in the extensions only running on
Firefox and Fennec branded browsers (and not on any re-branded ones
including versions like Iceweasel or Pale Moon). This can be worked
around by manually editing the cuddlefish.js file in the Add-on SDK
(for advanced users). See bugzilla bug #855651
for the patch.
Timeline: Fixed in the next major version (v24)
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