Version:           Quanta: 3.5.8 (using KDE KDE 3.5.8)
Installed from:    Gentoo Packages
Compiler:          gcc version 4.2.2 (Gentoo 4.2.2 p1.0) Configured with: /var/tmp/portage/sys-devel/gcc-4.2.2/work/gcc-4.2.2/configure --prefix=/usr --bindir=/usr/i686-pc-linux-gnu/gcc-bin/4.2.2 --includedir=/usr/lib/gcc/i686-pc-linux-gnu/4.2.2/include --datadir=/usr/share/gcc-data/i686-pc-linux-gnu/4.2.2 --mandir=/usr/share/gcc-data/i686-pc-linux-gnu/4.2.2/man --infodir=/usr/share/gcc-data/i686-pc-linux-gnu/4.2.2/info --with-gxx-include-dir=/usr/lib/gcc/i686-pc-linux-gnu/4.2.2/include/g++-v4 --host=i686-pc-linux-gnu --build=i686-pc-linux-gnu --disable-altivec --enable-nls --without-included-gettext --with-system-zlib --disable-checking --disable-werror --enable-secureplt --disable-libunwind-exceptions --disable-multilib --enable-libmudflap --disable-libssp --disable-libgcj --with-arch=i686 --enable-languages=c,c++ --enable-shared --enable-threads=posix --enable-__cxa_atexit --enable-clocale=gnu
OS:                Linux

While trying to edit an existing CSS file with only the following entry:

#result.ajax-loading {
    background: url(http://84.110.216.46/images/spinner.gif) no-repeat center;
}

the application halts immediately after clicking OK (where normally the editor would start).
the url in question is valid and works.

when using a local copy of the image, i.e.:

#result.ajax-loading {
    background: url(images/spinner.gif) no-repeat center;
}

the application behaves correctly.

I've considered the possibility that Quanta might be trying to fetch the URL and that it takes it a while to complete,
however, the mentioned file is 1569 bytes long and Quanta doesn't "revive" after a reasonable wait period (2 minutes).