On Tue, Jan 15, 2019 at 04:21:06PM +0000, Bernt Lie wrote: > I???m still using LyX 2.3.1 on one PC. There appears to be a bug on Win 10 > 64bit, latest version. If I insert \oiint in a math expression, nothing is > displayed.
https://www.lyx.org/trac/ticket/8493 It will be fixed in next major (2.4.x) release. Not nice workaround but it should be at least visible if you have instant preview on and leave the math inset. Pavel