I just noticed that right now, it is very easy to mess up your budget if your localisation settings have a comma as currency separator. Entering a value of 10,50â,¬ must be entered as '10.50' to be displayed correctly as '10,50' in the budget cell. Entering '10,50' will result in a value of 1.050,00.
The dangerous part is, that selecting/highlighting any value in a budget cell and pressing <enter> will ignore the comma and result in 100x the correct amount being entered as the new value. Now the next cell is selected, and the problem repeats. Hitting <enter> several times in a row can quickly mess things up.
I have run into this problem in Firefox 50.1.0 on a Windows 7 machine.
EDIT: Restarting Firefox has apparently solved the problem. Very strange.
EDIT 2: Just happened again, refreshing the page fixed it.
That's really weird. I will definitely keep my eye out for it. Thanks for reporting.
Also if anyone else is encountering this, please let me know!
In my system, apart of the numpad (.) issue, is working as intended.
If I put 12.3â,¬ the system screws and put 123â,¬. If I put 12.345â,¬ the system put 12345â,¬.
But if I use the comma decimal 12,3â,¬ then the quantity noted is 12,3â,¬ as expected.
I think you should replace all "," introduced to "." in the input (I guess in the code the decimal separator is a dot point), and then show the number according the system localization and completely forget about "," as thousands separator.