kvijay460 - thanks for filing this
I noticed that you've mentioned running "Jenkins 2.7.4." Is that correct? Because, if so, I bet that's why stuff isn't working for you. I took a look at the plugin's pom.xml file, and it specifies a minimum Jenkins version of 2.60.3, here, on L54.
Are you able to move to a more up to date version of Jenkins itself? I'd recommend doing so anyway. Lots and lots of enhancements have gone in since 2.7.4, including a whole bunch of security enhancements that would be good to pick up.
In any event, I can't recreate it either.
Here it is running locally on my laptop, by building the plugin at the cloudbees-bitbucket-branch-source-2.4.0 tag, and running it in development mode via mvn hpi:run. That ends me up with Jenkins core 2.60.3:
I've also installed it to my more traditional system, which is running core 2.160 along with various beta-level plugins from the experimental update center:
kvijay460 Can't reproduce. I tried latest Jenkins 2.150.2 with bitbucket-branch-source 2.4.0 and bitbucket 1.8, I can see Bitbucket in the drop down and it can be configured just fine. Can you check if you have these plugins installed and loaded correctly? Also, any error during jenkins startup?