Twitter Inc. (TWTR)  could open at a two-and-a-half year high Thursday after it posted stronger-than-expected fourth quarter earnings even as the shutdown of fake accounts contributed to a drop in monthly users amid its crackdown on abusive posts and potential election meddling through social media.

Twitter said non-GAAP net income came in at 19 cents a share for the three months ending in December, up 72% from the same period in 2016, topping the Street consensus of 14 cents. Revenue for the quarter came in at $731.6 million, a 2% increase from the previous period, the company said, again ahead of analysts' forecasts of $686.1 million. Monthly active users on the site rose 4% to 330 million, the company said, but narrowly missed the Street consensus estimate of 332.5 million. 

"Q4 was a strong finish to the year," said CEO Jack Dorsey. "We returned to revenue growth, achieved our goal of GAAP profitability, increased our shipping cadence, and reached five consecutive quarters of double digit DAU growth. I'm proud of the steady progress we made in 2017, and confident in our path ahead."

Twitter shares were marked 26.7% higher in pre-market trading in New York Thursday, indicating an opening bell price of $34 per share, the highest since July 2015 and a move that would take its three-month gain past 60%. 

The company said the monthly active user numbers were hit by both a change in Apple Inc.'s Safari browser, "which affected approximately 2 million" users, as well as  previously-flagged efforts "to reduce malicious activity on the service, inclusive of spam, malicious automation, and fake accounts."

Twitter said it expects to be profitable on a non-GAAP basis by the end of this year, and see adjusted first quarter earnings of between $185 million and $205 million and and EDITDA margin of between 33% and 34%.