But the foundation's financials remained in good shape. Cash, cash equivalents and the organization's investments totaled $272 million in 2013, up 13% from the year before. With that in the bank, Mozilla could survive at its 2013 expense pace for just shy of four quarters if income suddenly vanished.
Yet Mozilla still faces a rough road, especially if 2013's pattern of flat revenue-versus-increasing expenses continues.
Firefox's share of the desktop browser market has slipped by 26%, or about 4.8 percentage points, in the past 12 months, according to metrics firm Net Applications, even as the global share of browsing from the desktop has fallen because of the move toward mobile devices.
Meanwhile, Firefox OS faces an uphill battle against ultra-cheap Android-derived devices in the emerging markets Mozilla has targeted.
Some analysts have begun to wonder whether Mozilla can be a long-term player in browsers, much less mobile.
"Mozilla's browser share is likely to shrink over time," contended Jan Dawson, principal analyst at Jackdaw Research, in an interview yesterday. "Because there are more costs to cover moves [like Firefox OS], it's stretched thinner than before. If its [browser] share shrinks, it will have less revenue, which means it can spend less on development. That may make its products less appealing to users, so fewer people use them."
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