The item Adwcleaner may have struggled with was for Firefox not Chrome.
Chrome can be different due to the fact Google now has the account for users which syncs back and forth browser data and settings so if something goes missing it gets downloaded back, try below slowly and line by line
Lets try with chrome, and with the Google account instructions from Google for if the user logs in to the Account.
A) (From Google)
Turn off sync
In the lower right corner of the screen, click your account picture.
Choose Settings.
In the “Users” section, click Advanced sync settings.
In the dialog that appears, uncheck the items you no longer want to sync.
Delete sync information from your account
You can delete your synced information from your Google Account at any time:
In the lower right corner of the screen, click your account picture.
Choose Settings.
In the "Users" section, click Google Dashboard.
In the window that opens, go to the "Chrome sync" section and click Stop sync and delete data from Google.
All the information that has been synced will be deleted from your Google Account. All of your bookmarks, apps, and extensions will stay on your Chromebook, but won’t show up on other Chromebooks you use.
B) Reset Chrome
Click on Chrome’s main menu button, represented by three horizontal lines .When the drop-down menu appears, select the option labeled Settings.
Chrome’s Settings should now be displayed in a new tab or window, depending on your configuration. Next, scroll to the bottom of the page and click on the Show advanced settings link
Chrome’s advanced Settings should now be displayed. Scroll down until the Reset browser settings section is visible, as shown in the example below. Next, click on the Reset browser settings button.
A confirmation dialog should now be displayed, detailing the components that will be restored to their default state should you continue on with the reset process. To complete the restoration process, click on the Reset button.
C) Clear Flash Player (worked out by another MR
)
The other area of this (and why Windows and Mac (OSX) can be affected) it is Chrome with Flash Player involved by the looks (depending on changes).
Also do this
Windows
Close all open web browsers
Click Start, then Control Panel
For Window 8 /8.1 right click on the Start Button and select Control Panel
Depending on the way the Control Panel is set, you may have to now go System and Security
Click Flash Player
Click the Advanced tab
Click Delete All...
Tick / Check the box to Delete All Site Data and Settings
Delete All Audio and Video License Files is unchecked
Click Delete Data
Close the Flash Player Settings Manager window
Start Chrome to test
Quads