Choose or Create Lexicon

[alex-rawlings-yyc]

• Users with no existing lexicon have little or no friction to create and start with a blank one
• Users that have Paratext 9 lexicon get a choice to create from Paratext 9 data
• Users have an option to sign into Lexbox to choose a lexicon
• Users have an option to open a local fieldworks lexicon
• [Future] Users can import a lexicon from a known file type (LIFT, Fieldworks backup?, )

[imnasnainaec]

Full feature depends on sillsdev/languageforge-lexbox#2394 and sillsdev/languageforge-lexbox#2403