Hi tim109, I thought the Avast Web Shield worked completely outside of Firefox. I don't know why it would affect copy/paste. Is there also an Avast extension running inside Firefox? You can view, disable, and often remove unwanted or unknown extensions on the Add-ons page. Either:

• Command+Shift+a (Windows: Ctrl+Shift+a)
• "3-bar" menu button (or Tools menu) > Add-ons
• type or paste about:addons in the address bar and press Enter/Return

In the left column of the Add-ons page, click Extensions. On the right side, find the "Manage Your Extensions" heading.

Then scan down the list -- anything from Avast here that you can try disabling?

JSCHER2000,

First, thank you for taking the time to reply to my inquiry. I did as you asked and looked at my extensions, (and also my plugins) I do not have anything from Avast. Here are my extensions (2) - Cisco Webex, - DuckduckGo Privacy Essentials Here are my plugins (3) - OpenH264 video codec Cisco - Shockwave flash - Widevine Content Decryption Module Google

I'll try disabling those extensions and plugins and leave Avast Web Sheild.. and i'll post the results.

JSCHER2000, Ok, so my tests identified something very interesting. I turned off ALL the extensions and plugins. I left the Web Sheild on. Same issue.

The only other setting I ever modified on the Avast is the "Scan secure connections" (I had turned it off)

So i tried turning it back on. And my copy paste issue is gone with the Web Shield Enabled. I checked both an HTTP and a HTTPS website. So i turned all my plugins and extensions back on. I tested again. "Copy and Paste" works as long as the "Scan secure connections" is enabled.

So the summary of my testing is: In Firefox, if Avast Web Sheild has the option for "Scanning secure connections" disabled, the copy and paste will stop working.

Let me know if there is anything more i can test to try to resolve this, because in my line of work, i cannot always keep the Avast scanning my encrypted data on https.

I cant help but wonder if there is some relationship between the scanning secure connections and the pboard service people kill to temporarily get this working.

Looking forward to your advise.

Is it possible that the web page has a script that modifies how the clipboard works, and Web Shield is stripping it out? I don't really know how to explain your result.

I dont think so. The result is the same on all web pages. I'll test this on another mac (fresh install tomorrow) to see if i can repeat it.

Boot the computer in Windows Safe Mode with network support (press F8 on the boot screen or hold down the Shift key) to see if that has effect.

• https://www.bleepingcomputer.com/tutorials/how-to-start-windows-in-safe-mode/
• https://www.7tutorials.com/4-ways-boot-safe-mode-windows-10

Thanks for all your replies. cor-el .. just a quick note to you.. I'm using a Mac but I understand what your getting at.

Update 1. I tried the setup on a new mac, no issues what so ever. 2. I tried with the extensions disabled. Same issues 3. I suspect now, my FF profile. Its the only thing that is unique to this error. - I removed my profile entirely, and it seems to work normally. - I imported my bookmarks, etc but not everything and its still working. - the last time i fixed this using another method it came back a day later after something refreshed. I will let you know tomorrow if this turns out to be a corrupt profile.

Thanks again