This bug was found when testing per the sixth and seventh comment at Bug 53708
It seems somewhat heisenbuggy and I haven't been able to reproduce it yet. However, I'm sure of the steps which caused it.
Reporting this so that it's documented in case it is ever seen again.

System Environment:
Windows7 X64 SP1
Google Chrome 29.0.1547.66 m

Test Url:
https://www.mediawiki.org/wiki/Project:Sandbox?veaction=edit

Steps to reproduce:
Enable ULS IME hindi (hi) transliteration (labelled लिप्यंतरण)
Input the following:
agar[SPACE][SPACE][BACKSPACE]

What happens:
Apart from a bunch of buggy behaviour (described in the seventh comment at Bug 53708 ), the following console error shows up once the [BACKSPACE] is pressed:

Uncaught Error: ve.dm.Document.getNodeFromOffset(): offset 804 is out of bounds load.php?debug=false&lang=hi&modules=ext.visualEditor.core%2Cdata%2Cexperim…PageTarget.icons-vector%7Crangy&skin=vector&version=20130919T025548Z&*:106
ve.dm.Document.getNodeFromOffset load.php?debug=false&lang=hi&modules=ext.visualEditor.core%2Cdata%2Cexperim…PageTarget.icons-vector%7Crangy&skin=vector&version=20130919T025548Z&*:106
ve.dm.Surface.change load.php?debug=false&lang=hi&modules=ext.visualEditor.core%2Cdata%2Cexperim…wPageTarget.icons-vector%7Crangy&skin=vector&version=20130919T025548Z&*:84
ve.ce.Surface.onSelectionChange load.php?debug=false&lang=hi&modules=ext.visualEditor.core%2Cdata%2Cexperim…PageTarget.icons-vector%7Crangy&skin=vector&version=20130919T025548Z&*:275
oo.EventEmitter.emit load.php?debug=false&lang=hi&modules=ext.visualEditor.base%2Cmediawiki%2Cvi…ck%7Coojs%7Cunicodejs.wordbreak&skin=vector&version=20130919T025548Z&*:139
ve.ce.SurfaceObserver.pollOnceInternal load.php?debug=false&lang=hi&modules=ext.visualEditor.core%2Cdata%2Cexperim…PageTarget.icons-vector%7Crangy&skin=vector&version=20130919T025548Z&*:292
ve.ce.SurfaceObserver.pollOnce load.php?debug=false&lang=hi&modules=ext.visualEditor.core%2Cdata%2Cexperim…PageTarget.icons-vector%7Crangy&skin=vector&version=20130919T025548Z&*:291
ve.ce.SurfaceObserver.timerLoop load.php?debug=false&lang=hi&modules=ext.visualEditor.core%2Cdata%2Cexperim…PageTarget.icons-vector%7Crangy&skin=vector&version=20130919T025548Z&*:290
proxy load.php?debug=false&lang=hi&modules=jquery%2Cmediawiki%2CSpinner%7Cjquery.…l%7Cmw.MwEmbedSupport&only=scripts&skin=vector&version=20130912T173512Z:10

The file urls are:

For the last line:
https://bits.wikimedia.org/www.mediawiki.org/load.php?debug=false&lang=hi&modules=jquery%2Cmediawiki%2CSpinner%7Cjquery.triggerQueueCallback%2CloadingSpinner%2CmwEmbedUtil%7Cmw.MwEmbedSupport&only=scripts&skin=vector&version=20130912T173512Z

For all other lines:
https://bits.wikimedia.org/www.mediawiki.org/load.php?debug=false&lang=hi&modules=ext.visualEditor.core%2Cdata%2Cexperimental%2Cicons-vector%7Cext.visualEditor.viewPageTarget.icons-vector%7Crangy&skin=vector&version=20130919T025548Z&*

Also, the template's formatting was gone with the input hindi text appearing alongside the template text.

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**Version**: unspecified
**Severity**: normal