Thanks Moini for jumping in.
Allow me to sort all, because it‘s a little bit confusing.
Here some screenshots:
1. is the original file '1.svg' (64 x 64)
2. is the file modified (from 1.svg) with Illustrator (size and colors) 'ill-1-170x384.svg'. When I insert this file in the canvas of my webapp it appears correctly
3. is the file modified (from 1.svg) with Inkscape (size and colors) 'inkscape17_170x384.svg'. When I insert this file into the canvas I get the gray bar, moved to the left - see screenshot 4
4. is how it looks on my canvas after inserting the modified files. Left the file, created with Illustrator (screen 2) and right the file, created with Inkscape (screen 3)
So for me it seems, that the issue is caused by using Inkscape, something must me different in the way to handle and save it after changing size and color, because, if I use Illustrator I don't get this error.
For comparing: you'll find original (1.svg), Illustrator modified SVG (ill-1-170x384.svg) and Inkscape modified SVG (inkscape17_170x384.svg) files below