Type about:addons<enter> in the address bar to open your Add-ons Manager. Hot key; (<Control> [Mac=<Command>] <Shift> A)

In the Add-ons Manager, on the left, select Extensions. Remove “ ebay “ Anything.

Also remove SafeSearch, SearchAssist Incognito, FileConverter Addon, SearchLock, DiscreteSearch, WebSearch, Findwide Search Engine

Now do the same in the computer’s Programs Folder.

Windows: Start > Control Panel > Uninstall Programs. Mac: Open the Applications folder. Linux: Check your user manual.

Hi and thanks. Checked the extensions and ebay does not appear.

Also checked plug-ins and no ebay there either.

Does not appear in the uninstall programmes list either.

Hi MikeUser, this is not just a one-shot "sent to eBay for no apparent" reason problem, your default search engine is changed going forward as well?

Q: Do you generally search using the address bar, or the optional short search bar, or one of Firefox's other bars/boxes?

I'm aware of one way to accidentally make eBay or another one-click search engine the default in the short search bar:

With the cursor in the search box, press Ctrl+Down Arrow or Ctrl+Up Arrow to change your default to the next/previous in the list. You should see the icon changing at the top just below the search bar.

I don't know if that occurs with other search bars/boxes (it shouldn't happen with the address bar).

Cheers. No what happens is I do a (normal) search in the optional short search bar and get a load of search returns via ebay (instead of my preferred search engine).

I then go into options, check the default search engine and find it is 'ebay'. Change it back. For the next days/weeks all is fine and then suddenly the same thing happens.

Have just tried the ctl/up-arrow you describe and yes it pans through the various engines, but that's not what I've been doing to cause the change.

https://support.mozilla.org/en-US/kb/how-to-fix-preferences-wont-save

Note: Some software, like Advanced SystemCare with Surfing Protection, can protect files in the Firefox profile folder against changes. If you have such software then check the settings or uninstall this software.

Aha!

Happened again but... I've been logged in to ebay's website. I think I smell a rat! Ebay is clearly changing my firefox preferences. How do I prevent that?

Websites cannot directly change your default search engine. They would need to do it by enticing you to install an add-on or download some software.

A website should not be able to change browser settings. At least not without your knowing about it.

Type about:support in the address bar and press Enter. Under the main banner, press the button; Copy Text To Clipboard.. Now in the Reply Box on the forum page, do a right-click in the box and select Paste.

This will show us your system details. No Personal Information Is Collected.

You may have ad/mal-ware. Further information can be found in this article; https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-caused-malware?cache=no

Run most or all of the listed malware scanners. Each works differently. If one program misses something, another may pick it up.

Application Basics

Name: Firefox Version: 63.0.3 Build ID: 20181114214635 Update Channel: release User Agent: Mozilla/5.0 (Windows NT 6.2; Win64; x64; rv:63.0) Gecko/20100101 Firefox/63.0 OS: Windows_NT 6.2 Multiprocess Windows: 2/2 (Enabled by default) Web Content Processes: 3/4 Enterprise Policies: Inactive Google Key: Found Mozilla Location Service Key: Found Safe Mode: false

Crash Reports for the Last 3 Days

All Crash Reports Firefox Features

Name: Application Update Service Helper Version: 2.0 ID: [email protected]

Name: Firefox Screenshots Version: 33.0.0 ID: [email protected]

Name: Form Autofill Version: 1.0 ID: [email protected]

Name: Photon onboarding Version: 1.0 ID: [email protected]

Name: Pocket Version: 1.0.5 ID: [email protected]

Name: Web Compat Version: 2.0.1 ID: [email protected]

Name: WebCompat Reporter Version: 1.0.0 ID: [email protected]

Extensions

Name: Avast Online Security Version: 18.3.24 Enabled: false ID: [email protected]

Name: Avast SafePrice Version: 12.0.579 Enabled: false ID: [email protected]

Security Software

Type: Avast Antivirus

Type: Avast Antivirus

Type: Windows Firewall

Graphics

Features Compositing: Direct3D 11 (Advanced Layers) Asynchronous Pan/Zoom: wheel input enabled; scrollbar drag enabled; keyboard enabled; autoscroll enabled WebGL 1 Driver WSI Info: EGL_VENDOR: Google Inc. 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and the last few lines which were over the posting limit above:

OES_compressed_ETC2_RGB8_texture OES_compressed_ETC2_RGBA8_texture OES_compressed_ETC2_punchthroughA_RGBA8_texture OES_compressed_ETC2_punchthroughA_sRGB8_alpha_texture OES_compressed_ETC2_sRGB8_alpha8_texture OES_compressed_ETC2_sRGB8_texture WebGL 2 Extensions: EXT_color_buffer_float EXT_texture_filter_anisotropic EXT_disjoint_timer_query OES_texture_float_linear WEBGL_compressed_texture_s3tc WEBGL_compressed_texture_s3tc_srgb WEB

You may have ad/mal-ware. Further information can be found in this article; https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-caused-malware?cache=no

Run most or all of the listed malware scanners. Each works differently. If one program misses something, another may pick it up.

I have run all 5 scanners. No malware found.