This is the information I get when starting firefox. As I've read in other bugs, it may be because of an update. I've already tried to run pipelight-plugin --update, but it still won't install. Thank you very much!
[PIPELIGHT:LIN:unknown] attached to process.
[PIPELIGHT:LIN:unknown] checking environment variable PIPELIGHT_SILVERLIGHT5_1_CONFIG.
[PIPELIGHT:LIN:unknown] searching for config file pipelight-silverlight5.1.
[PIPELIGHT:LIN:unknown] trying to load config file from '/home/francisco/.config/pipelight-silverlight5.1'.
[PIPELIGHT:LIN:unknown] trying to load config file from '/etc/pipelight-silverlight5.1'.
[PIPELIGHT:LIN:unknown] trying to load config file from '/usr/share/pipelight/configs/pipelight-silverlight5.1'.
[PIPELIGHT:LIN:unknown] sandbox not found or not installed!
[PIPELIGHT:LIN:silverlight5.1] using wine prefix directory /home/francisco/.wine-pipelight.
[PIPELIGHT:LIN:silverlight5.1] checking plugin installation - this might take some time.
[install-dependency] wine-silverlight5.1-installer is already installed in '/home/francisco/.wine-pipelight'.
[install-dependency] wine-mpg2splt-installer is already installed in '/home/francisco/.wine-pipelight'.
[install-dependency] Ignoring deprecated wine-wininet-installer.
fixme:winediag:start_process Wine Staging 1.9.7 is a testing version containing experimental patches.
fixme:winediag:start_process Please mention your exact version when filing bug reports on winehq.org.
wine: DLL not found.
err:wineboot:ProcessRunKeys Error running cmd L"C:\\windows\\system32\\winemenubuilder.exe -a -r" (1157)
[PIPELIGHT:WIN:silverlight5.1] embedded mode is on.
[PIPELIGHT:WIN:silverlight5.1] windowless mode is off.
[PIPELIGHT:WIN:silverlight5.1] linux windowless mode is off.
[PIPELIGHT:WIN:silverlight5.1] force SetWindow is off.
[PIPELIGHT:WIN:silverlight5.1] window class hook is on.
[PIPELIGHT:WIN:silverlight5.1] strict draw ordering is off.
[PIPELIGHT:LIN:silverlight5.1] common.c:162:receiveCommand(): unable to receive data within the specified timeout.
[PIPELIGHT:LIN:silverlight5.1] basicplugin.c:128:attach(): error during the initialization of the wine process - aborting.
[PIPELIGHT:WIN:silverlight5.1] replaced API function CreateWindowExA.
[PIPELIGHT:WIN:silverlight5.1] replaced API function CreateWindowExW.
[PIPELIGHT:WIN:silverlight5.1] replaced API function TrackPopupMenuEx.
[PIPELIGHT:WIN:silverlight5.1] replaced API function TrackPopupMenu.
fixme:ntdll:EtwRegisterTraceGuidsW (0x7b8d2127, 0x7b970120, {aa087e0e-0b35-4e28-8f3a-440c3f51eef1}, 1, 0x71f478, (null), (null), 0x7b970120): stub
fixme:ntdll:EtwRegisterTraceGuidsW register trace class {aa087e0e-0b35-4e28-8f3a-440c3f51eef1}
[PIPELIGHT:WIN:silverlight5.1] init successful!
