Bug 498012

All based on the - maybe wrong - observation that I cannot customize the key to "on the fly" polygonal selection of the freehand selection tool. (by default ctrl).
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My sorry, long story:
I have a shortcut conflict which shows what to me is a flaw:
I use ctrl to activate line tool and.
Thus, I cannot use the "on the fly" polygonal mode of the freehand selection tool, because instead of allowing me to make straight lines in my selection, it will interrupt my precious ongoing selection to switch to line tool.

But if in the middle of a (always laborious...) freehand selection, shouldn't the line tool be deactivated? Who would want to draw in the middle of selecting stuff?
I guess it would also be the same for other accidental tool invocations that would silently throw away the ongoing selection?

Otherwise, maybe being able to customise which modifier activates the "on the fly" polygonal behavior would help working around that.
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Steps to reproduce:
- bind Activate line tool to ctrl left click in the tool invocations
- start a freehand selection tool
- try to continue in polygonal mode
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Observed result:
I start my freehand selection, i try to enter in polygonal mode on the fly, I lose my selection and have the line tool activated.
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Expected:
- I go into polygonal selection mode because freehand selection tool has priority over tool invocations.
- If not, I can configure the modifier to enter into polygonal mode
- I always expect hot coffee
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I didn't put it in tools/selection because to me the selection does what it's told, it's rather about how things are articulated and customizable for the user.