Syntax error

The first attempt to EXPORT an OTF was tested and worked OK.
Then a few amendments were made; particularly changing LSB & RSB of Metrics.
By 2nd attempt to Export… the application surprisingly shows this notification:
SYNTAX ERROR at: “}” … /features 42

This message says that there is something wrong with the feature file that Glyphs generated to use it to generate the font.

There are several reasons that can cause this problem.
This one looks like if you have incomplete Kerning.
Can you add one or two more pairs?

Or did you add some classes with illegal names. Have a look at the G: fields in the info box if they only contain letters or numbers.

If that does not help, can you send us the file?

Yes please send us the file, so I can update the handbook.
If you did not write your own feature code, I suspect a glyph or group name contains a feature code token, possibly ‘[’, ‘}’ or ‘;’.

There was no interference or writing any code, I also did not use any scripts as I apparently am long years user of Fontlab; but still a primitive user of Glyphs.
I will email you two different files that have the same problem;
Which email?

The mail to “support” at this domain.

I believe have found the problem;
Before generating OTF of a Hebrew Font; the following glyphs (FB20-FB28) /ayinaltone-hb/widealef-hb/widedalet-hb/widehe-hb/widekaf-hb/widelamed-hb/finalwidem em-hb/wideresh-hb/widetav-hb
which are NOT compulsory to exist in every Hebrew typeface (Mostly not used in cursive & calligraphic styles);
I kept them empty as the case is possible in Fontlab;
Though it seems GlyphsApp do not export empty named glyphs.
I’ve made a test by drawing a quick replacement shapes for the above mentioned glyphs; the ERROR message did not appear again. Then another test, by simply removing all those glyphs; thus EXPORT worked smoothly.
Thanks anyway