Start Firefox in Safe Mode {web Link} by holding down the <Shift>
(Mac Options) key, and then starting Firefox. Is the problem still there?

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Application Basics

Name: Firefox Version: 42.0 Build ID: 20151030084315 User Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:42.0) Gecko/20100101 Firefox/42.0 Multiprocess Windows: 0/1 (default: false) Safe Mode: false

Crash Reports for the Last 3 Days

All Crash Reports

Extensions

Name: Ubuntu Modifications Version: 3.2 Enabled: true ID: ubufox@ubuntu.com

Graphics

Adapter Description: Intel Open Source Technology Center -- Mesa DRI Intel(R) 945GM Asynchronous Pan/Zoom: none Device ID: Mesa DRI Intel(R) 945GM Driver Version: 1.4 Mesa 10.5.2 GPU Accelerated Windows: 0/1 Basic (OMTC) Blocked for your graphics card because of unresolved driver issues. Supports Hardware H264 Decoding: false Vendor ID: Intel Open Source Technology Center WebGL Renderer: Blocked for your graphics card because of unresolved driver issues. windowLayerManagerRemote: true AzureCanvasBackend: cairo AzureContentBackend: cairo AzureFallbackCanvasBackend: none AzureSkiaAccelerated: 0 CairoUseXRender: 1

Important Modified Preferences

browser.cache.disk.capacity: 204800 browser.cache.disk.filesystem_reported: 1 browser.cache.disk.smart_size.first_run: false browser.cache.frecency_experiment: 4 browser.download.importedFromSqlite: true browser.places.smartBookmarksVersion: 7 browser.privatebrowsing.autostart: true browser.startup.homepage_override.buildID: 20151030084315 browser.startup.homepage_override.mstone: 42.0 dom.apps.reset-permissions: true dom.mozApps.used: true extensions.lastAppVersion: 42.0 gfx.blacklist.direct2d: 4 gfx.blacklist.direct3d11angle: 4 gfx.blacklist.dxva: 4 gfx.blacklist.layers.direct3d10: 4 gfx.blacklist.layers.direct3d10-1: 4 gfx.blacklist.layers.direct3d11: 4 gfx.blacklist.layers.direct3d9: 4 gfx.blacklist.layers.opengl: 4 gfx.blacklist.stagefright: 4 gfx.blacklist.webgl.angle: 4 gfx.blacklist.webgl.msaa: 4 gfx.blacklist.webgl.opengl: 4 media.gmp-gmpopenh264.lastUpdate: 1448458174 media.gmp-gmpopenh264.version: 1.5.1 media.gmp-manager.buildID: 20150629114848 media.gmp-manager.lastCheck: 1448458174 network.cookie.prefsMigrated: true network.predictor.cleaned-up: true places.history.expiration.transient_current_max_pages: 11683 plugin.disable_full_page_plugin_for_types: application/pdf plugin.importedState: true privacy.cpd.offlineApps: true privacy.cpd.siteSettings: true privacy.sanitize.migrateFx3Prefs: true

Important Locked Preferences

JavaScript

Incremental GC: true

Accessibility

Activated: false Prevent Accessibility: 0

Library Versions

NSPR Expected minimum version: 4.10.10 Version in use: 4.10.10

NSS Expected minimum version: 3.19.4 Basic ECC Version in use: 3.19.4 Basic ECC

NSSSMIME Expected minimum version: 3.19.4 Basic ECC Version in use: 3.19.4 Basic ECC

NSSSSL Expected minimum version: 3.19.4 Basic ECC Version in use: 3.19.4 Basic ECC

NSSUTIL Expected minimum version: 3.19.4 Version in use: 3.19.4

Experimental Features

Sandbox

Seccomp-BPF (System Call Filtering): true Seccomp Thread Synchronization: true User Namespaces: true Media Plugin Sandboxing: true

Constantly Crashes many times with Ubuntu. I wonder what is the main cause. Is it Ubuntu or Firefox itself.

Have you tried the Linux version from www.mozilla.org/firefox/all to help rule out whether it is the Ubuntu version of Firefox that has issues or not.