[LyX/master] Disable properly math inset locking

[Jean-Marc Lasgouttes]

commit 94118b865e242dc4003967433fe41c7a29e40e98
Author: Jean-Marc Lasgouttes <lasgouttes at lyx.org>
Date:   Thu Dec 7 17:21:45 2023 +0100

    Disable properly math inset locking
    
    It is not clear whether this feature was once documented and used (it
    would have been 20 years ago).
    
    It is mostly disable now, but there was a remaining bit that is
    annoying now.
    
    I'll try to restore this later.
---
 src/mathed/InsetMathNest.cpp |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/src/mathed/InsetMathNest.cpp b/src/mathed/InsetMathNest.cpp
index 901cc36..37bbd40 100644
--- a/src/mathed/InsetMathNest.cpp
+++ b/src/mathed/InsetMathNest.cpp
@@ -1147,6 +1147,8 @@ void InsetMathNest::doDispatch(Cursor & cur, FuncRequest & cmd)
 		}
 		break;
 
+#if 0
+// FIXME: resurrect this later
 	// 'Locks' the math inset. A 'locked' math inset behaves as a unit
 	// that is traversed by a single <CursorLeft>/<CursorRight>.
 	case LFUN_INSET_TOGGLE:
@@ -1154,6 +1156,7 @@ void InsetMathNest::doDispatch(Cursor & cur, FuncRequest & cmd)
 		lock(!lock());
 		cur.popForward();
 		break;
+#endif
 
 	case LFUN_SELF_INSERT:
 		// special case first for big delimiters