some traditional Chinese don't render

[How]

䕶 this character using MicroHei font does not show on canvas, it is blank. It shows in text editing dialogs. This character also shows when this inkscape svg file is opened with eog image viewer.

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Inkscape version 0.91
Linux mint 17.1

[How (wonghow)]

䆺 this character also don't show

[How (wonghow)]

護 I am not sure why this one works. 䕶 this one doesn't inkscape but shows in other software

[su_v (suv-lp)]

Please add information about OS/platform to the bug description, thank you.

To ease testing on other systems, please attach a test case which exposes the reported issues, and details about any specific font needed to be installed on the local system (ideally, for a font with a free and open license, also a download URL) to display the text correctly.

[How (wonghow)]

護 I am not sure why this one works. 䕶 this one doesn't inkscape but shows in other software

Linux mint 17.1

MicroHei font can be installed from ubuntu repo

[su_v (suv-lp)]

https://en.wikipedia.org/wiki/CJK_Unified_Ideographs

CJK Unified Ideographs (Unicode block):
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護 - CJK UNIFIED IDEOGRAPH-8B77, Unicode: U+8B77, UTF-8: E8 AD B7
http://www.unicode.org/cgi-bin/GetUnihanData.pl?codepoint=8B77

CJK Unified Ideographs Extension A:
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䆺 - CJK UNIFIED IDEOGRAPH-41BA, Unicode: U+41BA, UTF-8: E4 86 BA
http://www.unicode.org/cgi-bin/GetUnihanData.pl?codepoint=41BA
䕶 - CJK UNIFIED IDEOGRAPH-4576, Unicode: U+4576, UTF-8: E4 95 B6
http://www.unicode.org/cgi-bin/GetUnihanData.pl?codepoint=4576

Fallback fonts:
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Pango/fontconfig font fallback seems to work ok for characters defined in the Unicode block, but apparently fails with characters defined in Extension A for (normal|medium) font styles. For text using fonts with styles like 'Thin', 'Light', 'Semi-Bold', 'Bold', 'Heavy' the fallbacks seem to work as expected. AFAICT this is not specific nor limited to Inkscape (same results e.g. when using rsvg-view-3 with same fontconfig and SVG file).