I don't know whether the problem originates in Safari but the message seems to indicate that it does.
I'm using OSX 10.9.3 on a Mac Mini and this occurs at start-up. The only application that is running at that point as far as I know is Trusteer Rapport. It is only recently that Rapport has started launching Safari to display a page saying that it has installed successfully every time I start up the computer. That was one of the reasons why I decided to have a look at the system log and found the error messages.
I tried downloading and re-installing Rapport to see if the problem went away but the same errors are still in the log. This is a longer extract from the log this morning:
014-07-02 22:52:59 +0100 rapportd[601]: objc[601]: Class application_notofications is implemented in both /Library/Rapport/bin/rapportd.app/Contents/MacOS/rapportd and /Library/Rapport/bin/RapportKobo6.dylib. One of the two will be used. Which one is undefined.
2014-07-02 22:52:59 +0100 rapportd[601]: objc[601]: Class application_notofications is implemented in both /Library/Rapport/bin/rapportd.app/Contents/MacOS/rapportd and /Library/Rapport/bin/RapportKadkadai.dylib. One of the two will be used. Which one is undefined.
2014-07-02 22:52:59 +0100 rapportd[601]: objc[601]: Class application_notofications is implemented in both /Library/Rapport/bin/rapportd.app/Contents/MacOS/rapportd and /Library/Rapport/bin/RapportDaishi.dylib. One of the two will be used. Which one is undefined.
2014-07-02 22:53:03 +0100 kernel[0]: Safari (map: 0xffffff801a6c2780) triggered DYLD shared region unnest for map: 0xffffff801a6c2780, region 0x7fff8b000000->0x7fff8b200000. While not abnormal for debuggers, this increases system memory footprint until the target exits.
2014-07-02 22:53:03 +0100 WindowServer[85]: CGXSetWindowListSystemAlpha: Invalid window 52 (index 0/1)
2014-07-02 22:53:04 +0100 kernel[0]: com.apple.WebKit (map: 0xffffff801a6c21e0) triggered DYLD shared region unnest for map: 0xffffff801a6c21e0, region 0x7fff8aa00000->0x7fff8ac00000. While not abnormal for debuggers, this increases system memory footprint until the target exits.
2014-07-02 22:53:08 +0100 com.apple.launchd.peruser.501[165]: Exited with code: 255
2014-07-02 22:53:08 +0100 Safari[606]: CGWindowContextCreate: failed to create window context delegate.
2014-07-02 22:53:08 +0100 Safari[606]: CGWindowContextCreate: failed to create window context delegate.
2014-07-02 22:53:08 +0100 Safari[606]: CGContextSaveGState: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
2014-07-02 22:53:08 +0100 Safari[606]: CGContextResetCTM: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
2014-07-02 22:53:08 +0100 Safari[606]: CGContextResetClip: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
2014-07-02 22:53:08 +0100 Safari[606]: CGContextTranslateCTM: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
2014-07-02 22:53:08 +0100 Safari[606]: CGContextScaleCTM: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
2014-07-02 22:53:08 +0100 Safari[606]: CGContextSaveGState: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
2014-07-02 22:53:08 +0100 Safari[606]: clip: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
2014-07-02 22:53:08 +0100 Safari[606]: CGContextRestoreGState: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
2014-07-02 22:53:08 +0100 Safari[606]: CGContextTranslateCTM: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
2014-07-02 22:53:08 +0100 Safari[606]: CGContextTranslateCTM: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
2014-07-02 22:53:08 +0100 Safari[606]: CGContextRestoreGState: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
2014-07-02 22:53:08 +0100 Safari[606]: CGContextSynchronize: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.
My programming days are long behind me but I do know that a potential fatal error is not a good thing! Any help would be appreciated.