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Current behavior

This is the code:
pTooltip="Data elaborazione di riferimento" tooltipPosition="top"
Please tell us about your environment:
Windows 7, IE11
Angular version: 4.2.6
PrimeNG version: 4.1.0
Browser: IE 7
We have slow performance respect 4.0.3
Hello,
Could you please share more of your code? You can upload it to plunkr and provide us its link.
If you use tooltip in IE11 you will see that this is the behavior.
The code used is the same as version of PrimeNG 4.0.3
I have the same behavior in any use of tooltip in IE 11.
<div class="pull-right" pTooltip="some text" tooltipPosition="left">

using "primeng": "4.1.0",
This is the same in Edge as well. When this.tooltipText.innerHTML = null; (line 126) is hit, the Microsoft behaviour is to set the innerHTML/innerText to "null", then the next line appends the tool tip text to that. Our current work around is setting [escape]="false".
I do have the same problem with IE 11 and Edge on Win 10 prior to version 4.1.2.
I can still reproduce this also on the sample page: https://www.primefaces.org/primeng/#/tooltip
Did this issue got attention?
Duplicate #3490
Most helpful comment
This is the same in Edge as well. When this.tooltipText.innerHTML = null; (line 126) is hit, the Microsoft behaviour is to set the innerHTML/innerText to "null", then the next line appends the tool tip text to that. Our current work around is setting [escape]="false".