Hi,
UI keeps on loading and I can see below error in browser.

webadmin-0.js:422 Wed Mar 21 14:59:47 GMT+530 2018 com.google.gwt.logging.client.LogConfiguration
SEVERE: Possible problem with your *.gwt.xml module file.
The compile time user.agent value (gecko1_8) does not match the runtime user.agent value (safari).
Expect more errors.
com.google.gwt.useragent.client.UserAgentAsserter$UserAgentAssertionError: Possible problem with your *.gwt.xml module file.
The compile time user.agent value (gecko1_8) does not match the runtime user.agent value (safari).
Expect more errors.
at Unknown.L(webadmin-0.js)
at Unknown.oj(webadmin-0.js)
at Unknown.new pj(webadmin-0.js)
at Unknown.nj(webadmin-0.js)
at Unknown.nb(webadmin-0.js)
at Unknown.qb(webadmin-0.js)
at Unknown.eval(webadmin-0.js)

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Thanks,
Gobinda