feature/long-lines-and-font-locking cdaa3b51f1: Further minor improvements of documentation

[Gregory Heytings]

branch: feature/long-lines-and-font-locking
commit cdaa3b51f1500ca1d91452037efe68fa0f7808bc
Author: Gregory Heytings <gregory@heytings.org>
Commit: Gregory Heytings <gregory@heytings.org>

    Further minor improvements of documentation
    
    * src/xdisp.c (syms_of_xdisp) <fontification-functions>:
    * etc/NEWS: Further minor wording improvements.
---
 etc/NEWS    | 19 ++++++++++---------
 src/xdisp.c |  8 ++++----
 2 files changed, 14 insertions(+), 13 deletions(-)

diff --git a/etc/NEWS b/etc/NEWS
index 2259c0e766..2d1ca8e98d 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -334,18 +334,19 @@ Use something like 'M-x shell RET ssh <host> RET' instead.
 * Changes in Emacs 29.1
 
 ---
-** Emacs is now capable of editing files with very long lines.
-The display of long lines has been optimized, and Emacs should no
-longer choke when a buffer on display contains long lines.  The
-variable 'long-line-threshold' controls whether and when these display
+** Emacs is now capable of editing files with arbitrarily long lines.
+The display of long lines has been optimized, and Emacs no longer
+chokes when a buffer on display contains long lines.  The variable
+'long-line-threshold' controls whether and when these display
 optimizations are in effect.
 
 If you still experience slowdowns while editing files with long lines,
-this is due either to the current major mode or to one of the enabled
-minor modes.  Try disabling the minor modes, or turn on 'so-long-mode'
-or 'so-long-minor-mode', or visit the file with find-file-literally'
-instead of the usual 'C-x C-f'.  Another reason for slowdown could be
-line truncation, which you can turn off with 'C-x x t'.
+this is due to line truncation, or to one of the enabled minor modes,
+or to the current major mode.  Try turning off line truncation with
+'C-x x t', or try disabling all known slow minor modes with 'M-x
+so-long-minor-mode', or try disabling all known slow minor modes and
+the major mode with 'M-x so-long-mode', or visit the file with 'M-x
+find-file-literally' instead of the usual 'C-x C-f'.
 
 Note that the display optimizations in these cases may cause the
 buffer to be occasionally mis-fontified.
diff --git a/src/xdisp.c b/src/xdisp.c
index 3ef3c0d379..e13d68eab9 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -36656,10 +36656,10 @@ fontify a region starting at POS in the current 
buffer, and give
 fontified regions the property `fontified' with a non-nil value.
 
 Note that, when the buffer contains one or more lines whose length is
-above `long-line-threshold', the narrowing of the buffer is locked
-(see `narrow-to-region'), and these functions only have access to a
-small portion of the buffer around POS and cannot use `widen' to gain
-access to other portions of buffer text.  */);
+above `long-line-threshold', these functions only have access to a
+small portion of the buffer around POS, and cannot use `widen' to gain
+access to other portions of buffer text because the narrowing of the
+buffer is locked (see `narrow-to-region').  */);
   Vfontification_functions = Qnil;
   Fmake_variable_buffer_local (Qfontification_functions);