hello, could you go to the firefox menu ≡ > help ? > troubleshooting information, copy the contents of that page and paste them here into a reply on the forum? this might give us a clue what is going on...

Troubleshooting Information This page contains technical information that might be useful when you're trying to solve a problem. If you are looking for answers to common questions about Firefox, check out our support website. Application Basics Name Firefox Version 42.0 Build ID 20151029151421 Update History Update Channel release User Agent Mozilla/5.0 (Macintosh; Intel Mac OS X 10.10; rv:42.0) Gecko/20100101 Firefox/42.0 Profile Folder Enabled Plugins about:plugins Build Configuration about:buildconfig Memory Use about:memory Registered Service Workers about:serviceworkers Multiprocess Windows 0/1 (default: false) Safe Mode false Crash Reports for the Last 3 Days Report ID Submitted

All Crash Reports Extensions Name Version Enabled ID QuickJava 2.0.6.1-signed true {E6C1199F-E687-42da-8C24-E7770CC3AE66} Tiny JavaScript Debugger 1.1.3 true tinyjsdebugger@enigmail.net TrafficLight 0.2.23.1-signed true trafficlight@bitdefender.com Graphics Asynchronous Pan/Zoom none Device ID 0x0a26 GPU Accelerated Windows 1/1 OpenGL (OMTC) Supports Hardware H264 Decoding false Vendor ID 0x8086 WebGL Renderer Intel Inc. -- Intel HD Graphics 5000 OpenGL Engine windowLayerManagerRemote true AzureCanvasBackend skia AzureContentBackend quartz AzureFallbackCanvasBackend none AzureSkiaAccelerated 0 Important Modified Preferences Name Value browser.cache.disk.capacity 358400 browser.cache.disk.filesystem_reported 1 browser.cache.disk.hashstats_reported 1 browser.cache.disk.smart_size.first_run false browser.cache.disk.smart_size.use_old_max false browser.cache.frecency_experiment 1 browser.download.importedFromSqlite true browser.places.smartBookmarksVersion 7 browser.sessionstore.upgradeBackup.latestBuildID 20151029151421 browser.startup.homepage https://my.yahoo.com/;_ylt=A0LEV75FsvhUUXgA7N8lnIlQ;_ylu=X3oDMTEzM2pkdDNiBHNlYwNzcgRwb3MDMQRjb2xvA2JmMQR2dGlkA1lIUzAwMl8 browser.startup.homepage_override.buildID 20151029151421 browser.startup.homepage_override.mstone 42.0 dom.apps.reset-permissions true dom.mozApps.used true extensions.lastAppVersion 42.0 font.internaluseonly.changed false gfx.blacklist.direct2d 3 javascript.enabled false media.gmp-gmpopenh264.lastUpdate 1431530434 media.gmp-gmpopenh264.version 1.4 media.gmp-manager.buildID 20151029151421 media.gmp-manager.lastCheck 1447447597 network.auth.allow-subresource-auth 2 network.cookie.prefsMigrated true network.predictor.cleaned-up true places.database.lastMaintenance 1447259108 places.history.expiration.transient_current_max_pages 104858 plugin.disable_full_page_plugin_for_types application/pdf plugin.importedState true plugin.state.flash 0 plugin.state.java 0 print.print_bgcolor false print.print_bgimages false print.print_colorspace print.print_command print.print_downloadfonts false print.print_duplex 1515870810 print.print_evenpages true print.print_in_color true print.print_margin_bottom 0.5 print.print_margin_left 0.5 print.print_margin_right 0.5 print.print_margin_top 0.5 print.print_oddpages true print.print_orientation 0 print.print_page_delay 50 print.print_paper_data 0 print.print_paper_height 11.00 print.print_paper_name print.print_paper_size_type 1 print.print_paper_size_unit 0 print.print_paper_width 8.50 print.print_plex_name print.print_resolution 1515870810 print.print_resolution_name print.print_reversed false print.print_scaling 1.00 print.print_shrink_to_fit true print.print_to_file false print.print_unwriteable_margin_bottom 0 print.print_unwriteable_margin_left 0 print.print_unwriteable_margin_right 0 print.print_unwriteable_margin_top 0 privacy.cpd.downloads false privacy.cpd.formdata false privacy.cpd.history false privacy.cpd.sessions false privacy.sanitize.migrateFx3Prefs true privacy.sanitize.timeSpan 0 storage.vacuum.last.index 1 storage.vacuum.last.places.sqlite 1446919257 Important Locked Preferences Name Value JavaScript Incremental GC true Accessibility Activated false Prevent Accessibility 0 Library Versions Expected minimum version Version in use NSPR 4.10.10 4.10.10 NSS 3.19.4 Basic ECC 3.19.4 Basic ECC NSSSMIME 3.19.4 Basic ECC 3.19.4 Basic ECC NSSSSL 3.19.4 Basic ECC 3.19.4 Basic ECC NSSUTIL 3.19.4 3.19.4 Experimental Features Name ID Description Active End Date Homepage

thanks, it looks like you have turned off javascript indeed. in order to fix this, please enter about:config into the firefox address bar (confirm the info message in case it shows up) & search for the preference named javascript.enabled. double-click it and change its value to true.

Problem solved. Thank you very much.