[Feature request] More decimals for transactions (amount, fee, tax)

[Dathwada]

Is your feature request related to a problem? Please describe.

My problem is that the amount (shares x quote) does not have enough decimal places to represent a transaction where I received some small amounts of a cryptocurrency where the price was also very low at the time. These transactions have an amount of €0.00 and completely mess up the performance.

e.g. 1.45678 "shares" x 0.000234 €

I saw that you made changes to the decimal places for shares and security prices in v0.50.0 but didn't made those changes to amount, fee (#2312, #2518) and tax.

Describe the solution you'd like

The allowed decimal places for amount, fee and tax should also be increased to 8 digits.

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.

In my opinion, there is no other way in the long term.

Additional context
There are crypto exchanges that have fiat currencies with 8 digits.

When I was looking for a solution to my problem, I found many other people with the same or a similar problem in your forum:

https://forum.portfolio-performance.info/t/mehr-nachkommastellen-insgesamt-und-mehr-als-zwei-nachkommastellen-bei-konten/18542
https://forum.portfolio-performance.info/t/anzahl-der-nachkommastellen-bei-buchungen/4660
https://forum.portfolio-performance.info/t/einstandskurs-bei-pennystocks-fehler-durch-fehlende-nachkommastellen/6154
https://forum.portfolio-performance.info/t/numbers-with-more-than-two-decimals-are-cut-off/30138
https://forum.portfolio-performance.info/t/number-of-decimals/13096/9