Syntax highlight randomly stops being updated

[teo1978]

At random times it happens, while editing a text file in some programming language (I see it daily with PHP files), that:

- you are editing the file somewhere in the middle of it
- you type some unmatched opening quote, for example you start typing a string assignment. At this point all the syntax from where you are through the end of the file is screwed up, as expected (mostly "pink", or whatever the color of strings is)
- then when you do type the matching closing quote sign that was missing, and the syntax is now correct, a huge portion of the file still doesn't get refreshed, that is, it remains with the wrong screwed-up syntax highlight.

By moving the cursor somewhere in the part of the code whose syntax highlight hasn't been updated, usually the whole file gets properly syntax-highlighted again.

ProblemType: Bug
DistroRelease: Ubuntu 15.10
Package: gedit 3.10.4-0ubuntu13
ProcVersionSignature: Ubuntu 4.2.0-35.40-generic 4.2.8-ckt5
Uname: Linux 4.2.0-35-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.19.1-0ubuntu5
Architecture: amd64
CurrentDesktop: Unity
Date: Sat Apr 30 18:03:41 2016
InstallationDate: Installed on 2013-10-11 (931 days ago)
InstallationMedia: Ubuntu 13.04 "Raring Ringtail" - Release amd64 (20130424)
SourcePackage: gedit
UpgradeStatus: Upgraded to wily on 2016-01-18 (103 days ago)

[Sebastien Bacher (seb128)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. The issue you are reporting is an upstream one and it would be nice if somebody having it could send the bug to the developers of the software by following the instructions at https://wiki.ubuntu.com/Bugs/Upstream/GNOME. If you have done so, please tell us the number of the upstream bug (or the link), so we can add a bugwatch that will inform us about its status. Thanks in advance.

[Daniel van Vugt (vanvugt)]

Thank you for reporting this bug to Ubuntu.
Ubuntu 15.10 (wily) reached end-of-life on July 28, 2016.

See this document for currently supported Ubuntu releases:
https://wiki.ubuntu.com/Releases

We appreciate that this bug may be old and you might not be interested in discussing it any more. But if you are then please upgrade to the latest Ubuntu version and re-test. If you then find the bug is still present in the newer Ubuntu version, please add a comment here telling us which new version it is in and change the bug status to Confirmed.

[teo1978 (teo8976)]

Thank you for looking at the bug for the first time 2 years and a half after it was reported.

The issue is still present at least on 16.04.