I am afraid you have to ask help in Photoshop forum. I don't know how Photoshop determine whether this menu item should be disabled.
Thank you Carl, I posted in the Photoshop forum.
This is Zhihong from Adobe CEP team. Thanks for reporting this, could you please help to offer following information:
1. What is your Windows version and PS version?
2. Have you update PS from Adobe Creative Cloud? If so, is this problem a new problem after this update?
3. Could you please help to get the CEP log and listed in this thread? The steps are as following:
First, set the “LogLevel” value of registry key “HKEY_CURRENT_USER\Software\Adobe\CSXS.4” from “1” to “6”. Second, restart Photoshop and do the steps you listed. Then we will get CEP logs in “C:\Users\’username’\AppData\Local\Temp” path like csxs4-PHSP.log.
4. Could you please check following components version on your machine?
Version of CEPHtmlEngine.exe (it locates at path “C:\Program Files (x86)\Adobe\Adobe Photoshop CC\CEPHtmlEngine”).
Version of PlugPlugOwl.dll (it locates at path “C:\Program Files (x86)\Adobe\Adobe Photoshop CC”).
One more point: please check the folder “C:\Program Files (x86)\Common Files\Adobe\CEPServiceManager4\extensions” and make sure there are extensions (plugins) in this folder. If there is no extension in this folder, the PS “Extensions” menu will become gray.