Together let's do some process of elimination. As XenPorta did or does have a small conflict, it stands to reason there maybe another conflict. Now, I personally do not have XenPorta installed, so we can rule that out. What other add-ons do you have installed?
Here is my current list of "
official" add-ons from XenForo.com.
Let me know if you see something you have in common.
'Keywords' Meta Tag by xenCODE 1.0.0
8thos Google Authorship 1.5
8thos Style Selector in Sidebar 3.0
8thos Title URLs 1.0
Account Upgrade Reminder 0.1
Add Avatar to Quote 1.0.0 RC1
Add Poll to Existing Threads 1.0
Add User Avatar to Last Post by Waindigo 1.1.1
Add-on Builder 1.0
Add-on Installer 0.2
Advanced BBcodes Toolbar 3.2.0
Advanced User Promotions by Waindigo 1.0.3
Alexa Enhancer by xenCODE 1.0.0 Beta
Are You A Human? 4.0
Attachment Viewer 0.9.1
Auto Follow on Registration 2.0
Auto Ping by xenCODE 1.0.0 Beta 1
automatic online page reloader 1.0.0
Avatar for Banned Users 1.0
Avatar Gallery 0.1b
AzuCloud 0.1.2
BBcode MediaSites Pack 1.0.4
Brivium – Reset Password using Secret Question 1.0.1
Browser Detection (Mobile/MSIE) 1.1
Browser Update Notification 1.0
Clickable Rows 2.0.0
Cliptheapex.com's Countdown Timer 1.0.1
Conversation Manager 1.0.1
Copyright Notice by Waindigo 1.0.1
Create Thread on Warning 1.2
Custom BBCode Manager 1.3.4
Description for RSS 1.2
Developer Kit 1.1
Digital Point Thread/Post BBCode 1.0.0
Disallow Recent Activities for Guests 1.0.1
Disallow What's new Page for Guests 1.0.0
Display User Age 1.0
Double Post 1.0.5
Email Report 1.0.1
Enable Debug From Admin Home 1.1a
Extra Code Events 1.0.2
Find users sharing the same IP 0.0.2
ForumRunner for XenForo 1.1.3
FreddysHouse Tools: Signature Once 1.2.0
Friend Inviter 1.2
Friends by Waindigo 1.0.2
Global Create Thread Formular 1.0.2
Go To Top ! 1.1.2
GoodForNothing Url Redirector 1.0.3
Inactive User Mail Notifier 1.2
Include Banned Users to Total User Count 1.0.0
Instagram Media Site 1.1
IwDRP Total Forum Thread Views 1.1
Keyword Replace by Waindigo 1.0.1
Live Updates 2.0
Login As User by Waindigo 1.1.0
LoginUserLocks - Prevent attempts to brute force the login area 1.0.1
Magic Breadcrumb Arrow 2.0
Markitup XenForo Integration 2.1
Master Forums 1.0
Member Card View Permissions 1.0
Mobile Icons 1.0
Mobile Style Selector 1.2
Modifications Pack
Monthly Email 1.0.3
More Advanced User Upgrades by Waindigo 1.1.0
New User Notification System 2.1
No Hidden Users 1.0.0 RC1
Nodes As Tabs 1.1.3
Not Safe For Work 0.9.3
Notifications - powered by Gritter 1.5
Number of Posts to Send Personal Conversations 1.0
Picasa Slideshow 1.3
PinIt Share Button 1.0
Post Caching 0.9.4
Post Ratings 1.5.0
Premium Members BBcodes 1.4
Profile View Count 1.3
Public Mod Log 1.0.0 PL3
Quick Reply Preview 1.3
QuoteME ! 1.5
ragtek Contact Thread 2.0.0 Beta1
ragtek Custom Add-on 1 1.0.1
ragtek FrameWork 1.1.7
ragtek Profile Visitors 1.0.0 RC2
Registration Form Timer 2.0
Report Comment Alerts 1.0.0
Reset Password From ACP 1.0
Responsive Design 1.0.4
Route Changer 1.1.2b
Search Style Properties 1.0
Search This Thread 1.3
Set Default Signature for new Members 1.0.1
Set Rememer Me Cookie Time 1.0.1
Share Search URL 1.0.1 PL1
Show Attachment md5 Sum 1.0.0
Sitemap for XenForo 1.2.0
Smilie Importer by Waindigo 1.0.1
Social Beta 2
Social Groups by Waindigo 1.0.2
sonnb - Bulk importer for smilies management 1.0.4
sonnb - Prevent double post 1.0.1
sonnb - See post's links permission 1.1.1
sonnb - Stop Spam Here 1.2.2
sonnb - Stop Spam Here - Botscout API 1.0.0
sonnb - Stop Spam Here - FSpamlist API 1.0.0
sonnb - Stop Spam Here - SpamBusted API 1.0.0
sonnb - Stop Spam Here - Stop Forum Spam API 1.0.2
Start Conversation from Post Bit 1.3
Steam Auth 1.1.6
Stop Auto Linking Patch 0.9
Sypex Dumper 2 1.0
Tapatalk 1.4.0
Template Modification System 1.2
Thread Watchers 1.2
TinyMCE Enhancements 1.1
TinyMCE Fix 0.53
Toggle ME 2.1
UrlRewriter 1
vBulletin 4 Importer To XenForo 1.1 1.0
View Members Online Now Group Restriction 1.0
Widget Framework Widget Pack 1.0.1
XenFacil's WidgetFramework Renderers 1
XenFans.com - Popular Content 1.1.2
XenMerge 0.1 Beta
XenMoods 1.1.3
Xenplaza - Post Limit For link 1.1.0
XenSocialize by xenCODE 1.0.2
XF Arcade 0.0.8
XFA - BBCode for tabs 1.0.3
XFA - Better Blogs 1.0.9
XFA - Bump Thread 1.0.2
XFA - Unread alert count in favicon 1.3.0
[8wayRun.Com] XenMedio (Media) 1.5.3
[8wayRun.Com] XenUtiles (Tools) 1.2.2
[bd] Anonymous Posting 2.0
[bd] Banking 0.9.9.1
[bd] Delete Zero Posters beta 2
[bd] Facebook-style Password 0.9
[bd] Tag Me 1.6.6
[bd] Widget Framework 2.1
[ChipXF] Mobile Swicher 1.0
[Darth]Administrate Forum 1.0
[dc] Smiley Manager 1.1.0
[RT] User Rank Ribbons (15, w/TMS) 2.3
[Tinhte.vn] Wipe To Go 1.2
[Tinhte] Attach Image Optimization 2.2.8
[Tinhte] XenTag 1.3.4
[tLk] ReadPC 1.1.0
[WMTech] - Maintenance Screen 1.0.3
[xfr] User Albums 1.0.0 b7
[xfr] User Albums More 1.0.0
[YOU] hack 1.1.1