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Kill the XUL.mfl file for good

Avoiding the creation of the XUL.mfl file

Mozilla creates in its profile directory a file named XUL.mfl, which contains pre-compiled UI elements. This is meant to speed up the operation of Mozilla, however in a fileserver based environment, this can be problematic:

  • At several megabytes a pop, these files will take up a considerable amount of space, because each user has his own...
  • Loading these files from the server, and storing them back slows down the network, thus it may actually be faster without than with
  • XUL.mfl occasionnally gets corrupted, needing a manual intervention to wipe it out, before mozilla again works correctly.
  • With Quicklauncer (see above), mozilla's speed is actually quite adequate, even without XUL.mfl

For these reasons, it is desirable to disable the XUL.mfl functionality. Unfortunately, there appears to be no "clean" way of doing so (javascript command in prefs.js or registry setting). But creating a subdirectory named XUL.mfl in mozilla's profile directory seems to help (mozilla is not smart enough to remove the directory before creating the file, thus the presence of the directory effectively disables this (mis)feature).

N.B. It seems that as of version 1.5, the XUL.mfl file no longer is a problem, so this part may be skipped if you have a recent enough Mozilla version.

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 Contributors to this page: teoli, Kohei, Alain Knaff
 Last updated by: teoli,