SUMMARY
Moving among the several fields of the open/save menu by the TAB button of the keyboard  prevents from the possibility to reach again the field of the file name, if not by ctrl-TAB keys. In addition, once reached the file name in its own field by CTRL-TAB, all the name of the file is selected including its extension forcing to select again the noun of the file in order to change it. The reason why it's not possible to select again the whole file name is due to the sequence of the TAB steps enters a loop among the first folder listed in the menu, the select folder key, the download key, once the first folder listed in the menu is reached.

STEPS TO REPRODUCE
1. download any file from an any page of the browser, as example kde neon iso;
2. the menu to chose the position where to download the file appears;
3. switch by TAB, and look at the aforementioned issues.

OBSERVED RESULT
1) all the name of the file is selected including its extension forcing to select again the noun of the file in order to change it;
2) The sequence of the TAB steps enters a loop once the first folder listed in the menu is reached.

EXPECTED RESULT
1) only the name of the file is selected without its extension;
2) the sequence of the TAB steps doesn't enter a loop once the first folder listed in the menu is reached allowing to get the field of the file name again by TAB.

SOFTWARE/OS VERSIONS
Operating System: KDE neon 5.21
KDE Plasma Version: 5.21.5
KDE Frameworks Version: 5.81.0
Qt Version: 5.15.2
Kernel Version: 5.4.0-72-generic
OS Type: 64-bit
Graphics Platform: X11