I have problem Pixiv website after update the last version avast

[pianoalice]

Hello Avast Team ,I have problem after update the last version avast antivirus

left picture is close add-ons avast
right picture is open add-ons avast
I need know how to setting close square at red border because I have to try close all setting but it not work. thank you

*My Browser is Firefox
*picture from http://www.pixiv.net

[polonus]

Update: pixiv dot net has a hidden iframe: http://killmalware.com/pixiv.net/#
Sucuri detects: Hidden Iframes. Details: http://sucuri.net/malware/entry/MW:IFRAME:HD202?v02
<iframe name="topjack" id="topjack" src="-http://d.pixiv.org/show?zone_id=topjack&segments=noseg&format=html&pla_referer_page_name=pixiv&num=562eb215822" width="0" height="0">
Consider: http://www.domxssscanner.com/scan?url=https%3A%2F%2Fwww.secure.pixiv.net%2Flogin.php%3Freturn_to%3D%252F+tags.php%3Ftag%3Dpixiv%25E3%2583%2595%25E3%2582%25A1%25E3%2583%25B3%25E3%2582%25BF%25E3%2582%25B8%25E3%2582%25A2T
Suspicious on iFrame check:
Suspicious

-http://d.pixiv.org/show?zone_id=topjack&segments=noseg&format=html&pla_referer_page_name=pixiv&num=5'

Google Browser Diff: Not identical

Google: 51530 bytes       Firefox: 51122 bytes
Diff:         408 bytes

First difference:

Extermal links check:
Please check this list for unknown links on your website:

-https://booth.pm/  -->  'booth(簡単にネ'   secure!
-http://ja.curecos.com/?ref=pixiv-cool  -->  'コスプレcure' Insecure login (1)
Password will be transmited in clear to http://ja.curecos.com/login/
-http://worldcosplay.net/?ref=pixiv-cool  -->  'worldcosplay'
-https://halol.me/  -->  'halol' Insecure identifiers 88%

polonus