I am facing am issue with Salesforce Communities Using Napili Template and Winter'16 Version. I am able to create a question by clicking on the Ask a Question button,but I am unable to see the question in the topic detail page under discussions tab. Please check the below GIF. Thanks.
Finally figured out how to fix this. Here is how i fixed this:
Step1: Take a backup of Topic and Topic Assignments Sobject Records.
Step2: Delete all the Topics that you have on community. The associated SObject is named Topic. Warning: This will also delete the topic Assignments for the Topics.
Step3: Use the backup for Topic and Topic Assignments and insert those records back again.
Step4: Add the topics back to community manually from Community Management.
Thank you everyone in Community Implementation group and Mohith for helping me out on this.