Can be also reproduced with EE-3.3.0-maintenance branch r. 43351 (IE9).

I couldn't reproduce this issue. I tested it on both, a real IE9 (icepcvm-ie9) and IE11 in IE9 mode. I tested with the latest revision today as well as with revision 43351, as indicated above. I couldn't reproduce it in any of those cases. I couldn't reproduce it on the 4.0 trunk either. I tested with the AutoCompleteEntry only, facet and f:ajax test pages. Please verify that this issue is not reproducible anymore or provide more detailed testing environment details and instructions on how to reproduce it.

Still able to reproduce ICEfaces ee-3.3.0 maintenance branch r43829.

Still able to reproduce ICEfaces ee-3.3.0 maintenance branch r44437, using icepcvm-ie9 and the steps listed in the description.

I still haven't been able to reproduce this issue by myself, using the latest revision of the 3.3 EE maintenance branch on icepcvm-ie9. I remember I was able to see the issue if the app was deployed on your machine, Liana.

I have a couple of questions:

1) Do you see this issue everytime you type a character or only the first time you type a character after loading the page?

2) Are you navigating to the test page by going directly to http://localhost:8080/autoCompleteEntry/autoCompleteEntryOnly.jsf or are you first loading the welcome page http://localhost:8080/autoCompleteEntry/ and then clicking on the AutoCompleteEntry Only link?

Thanks

Tested with Icefaces EE-3.3.0 maintenance branch r44479.
Regarding Art's questions...
1.) I only see the issue after typing one single character into the autoCompleteEntry. Typing a second character makes the list stay open as expected. The retracting list only occurs the using the first time using autoCompleteEntryOnly.jsf .
2.) icepcvm-ie9 does not have any servers of it's own so I am using the application hosted from my machine. I go to the test page by opening IE 9, then typing http://My ip:8080/autoCompleteEntry. This loads the welcome page, from there I navigate to AutoCompleteEntry Only. I am also able to reproduce the issue by opening the browser and navigating directly to http://...../autoCompleteEntry/autoCompleteEntryOnly.jsf

r44487: committed an attempt to fix this issue by preventing the list from hiding on ie9 when the inField label is removed.

The issue seems to occur only when using the inField label, and it only happens the first time a character is typed. A full markup update of the component seems to be a condition for this to happen as well.

Please test again with this new fix and report if the problem is solved.

Note: after removing all characters the results displayed on ie9 are the very first ones in the list of all possible results. This is actually the correct behaviour, which is not present in the other browsers, but that issue is not related to this one.

r44497: removed previous attempts to fix the issue.

r44496: In JavaScriptContextSetup.java, moved the partial request conditional inside the <script> tag, so that it only applies to the script contents and the <script> tag is always rendered, whether it's a full or partial request; the end result is avoiding an extra update at the first partial request after the page has been loaded (i.e. updating the 'dynamic-code-compat' node without the <script> tag).

This issue only occurred when the compat jar was in the /lib folder of the app. In particular, the JavaScriptContextSetup event listener indirectly caused this situation. This event listener renders a span with the id 'dynamic-code-compat' and a script tag inside containing all the dynamic scripts. The script tag is only rendered when the request is not a partial request; this causes the 'dynamic-code-compat' node to be updated at the first partial request on the page without the script tag. That update itself (combined with other factors) was causing this issue on IE9. So, the JavaScriptContextSetup event listener was modified to always render the script tag itself, in order to avoid making that extra update, which is a slight performance improvement and avoids this issue with ace:autoCompleteEntry on IE9. It's still not clear how this update could've caused this issue on IE9, as it's very unrelated to the ace:autoCompleteEntry code, but, as we know from experience, IE browsers have their particular idiosyncrasies that make things not work as expected in many cases.

Tested with ICEfaces EE-3.3.0 maintenance branch r44497. Tomcat 7, IE 9, 11, FF 34, Chrome 41. The initial issue of the list retracting when using the autoCompleteEntry Only demo with IE 9 appears to be resolved however the demo stops functioning correctly after the first time inputting a character and this is seen in all browsers.
To reproduce:
1.) Use autoCompleteEntry Only QA test app or showcase > autoCompleteEntry > Overview on the EE-3.3.0 maintenance branch.
2.) Type one letter into the autoCompleteEntry and choose a selection from the list.
3.) Backspace all letters out. The list will display options starting with the initial letter you entered.
4.) Click away from the autoCompleteEntry to dismiss the list.
5.) Type one letter into the autoCompleteEntry, the list will no longer display.

The last issue seems to be caused by another recent commit in the framework core, under ICE-10524 (r44495). Testing with the latest revision and just reverting the core folder to r44494 doesn't show the issue.

Moved the recent regression to ICE-10524, which appears to be the root cause. Marking this resolved.

Tested with ICEfaces EE-3.3.0 maintenance branch r44536 using Tomcat 7 and IE 9.
I have come across another situation where the autoCompleteEntry list retracts prematurely. When using a required field, the list functions as expected the first time through. On the second attempt to enter input, the list will drop and then retract again.
To reproduce:
1.) Launch ICEfaces EE-3.3.0 showcase with IE 9.
2.) Navigate to ace:autoCompleteEntry > Required Styling.
3.) In the Required field type the letter a, the list of options will appear
4.) Without choosing an option, press backspace to clear the field. A validation message will appear.
5.) Type the letter s into the input. The list will open then retract.
6.) Typing a second letter into the input will prompt the list to display correctly.

We'll consider that last quirk a Known Issue for IE9. Seems minor.