First, let's explain why I want Firefox under wine, and not the Firefox that is shipped out of the box with Ubuntu.
I want to use Firefox under wine because I want to use the Widevine addon, which is "at this time not available for linux".
Here is what I did so far to install and use Firefox on wine.
On Ubuntu 12.04 LTS, I just installed wine like that:
sudo apt-get update; sudo apt-get install wine
Then I downloaded the windows installer for Firefox from the mozilla website.
I ran the Firefox Setup 25.0.exe file with wine but at the end of the install process when launching Firefox, I got a window notifying me that the program at crashed.
I ran Firefox from the command line with wine, to get an idea of what could have went wrong:
wine /home/myUser/.wine/drive_c/Program\ Files/Mozilla\ Firefox/firefox.exe
fixme:heap:HeapSetInformation (nil) 1 (nil) 0
fixme:process:SetProcessDEPPolicy (1): stub
fixme:iphlpapi:NotifyAddrChange (Handle 0x368e8fc, overlapped 0x368e8e0): stub
fixme:winsock:WSCGetProviderPath ({e70f1aa0-ab8b-11cf-8ca3-00805f48a192} 0x44fe6f8 0x44fe6b8 0x44fe6e4) Stub!
fixme:advapi:RegisterTraceGuidsW (0x1b0e290, 0x39ead80, {509962e0-406b-46f4-99ba-5a009f8d2225}, 3, 0x3974d00, (null), (null), 0x39eadb0,): stub
fixme:winsock:WSCGetProviderPath ({e70f1aa0-ab8b-11cf-8ca3-00805f48a192} 0x44fe6f8 0x44fe6b8 0x44fe6e4) Stub!
fixme:winsock:WSCGetProviderPath ({11058240-be47-11cf-95c8-00805f48a192} 0x44fe6f8 0x44fe6b8 0x44fe6e4) Stub!
fixme:winsock:WSCGetProviderPath ({11058241-be47-11cf-95c8-00805f48a192} 0x44fe6f8 0x44fe6b8 0x44fe6e4) Stub!
fixme:winsock:WSCGetProviderPath ({11058241-be47-11cf-95c8-00805f48a192} 0x44fe6f8 0x44fe6b8 0x44fe6e4) Stub!
fixme:ntdll:NtLockFile I/O completion on lock not implemented yet
fixme:advapi:SetNamedSecurityInfoW L"C:\\users\\myUser\\Application Data\\Mozilla\\Firefox\\Profiles\\cn4oy6kh.default\\extensions.ini" 1 536870916 (nil) (nil) 0x13d40c (nil)
fixme:imm:ImmReleaseContext (0x20022, 0x13e850): stub
fixme:win:EnumDisplayDevicesW ((null),0,0x32ee18,0x00000000), stub!
fixme:shell:ApplicationAssociationRegistration_QueryCurrentDefault (0x143b50)->(L"webcal", 1, 1, 0x32c7a0)
fixme:shell:ApplicationAssociationRegistration_QueryCurrentDefault (0x143b50)->(L"ircs", 1, 1, 0x32c7a0)
fixme:shell:ApplicationAssociationRegistration_QueryCurrentDefault (0x143b50)->(L"mailto", 1, 1, 0x32c7a0)
fixme:shell:ApplicationAssociationRegistration_QueryCurrentDefault (0x143b50)->(L"irc", 1, 1, 0x32c7a0)
fixme:alsa:AudioSessionControl_SetGroupingParam (0x153050)->({7b0a93ee-05e7-4576-9cc5-64fdf201f303}, (null)) - stub
fixme:alsa:AudioSessionControl_SetGroupingParam (0x153050)->({00000000-0000-0000-0000-000000000000}, (null)) - stub
fixme:alsa:AudioSessionControl_UnregisterAudioSessionNotification (0x153050)->(0x6311880) - stub
wine: Call from 0x7b839cf2 to unimplemented function dwmapi.dll.DwmGetCompositionTimingInfo, aborting
fixme:dbghelp:elf_search_auxv can't find symbol in module
Unfortunately I don't know what to do from there on...