words added to dictionary aren't saved between sessions

Version: 5.3.0.3 (x64)
Build ID: 7074905676c47b82bbcfbea1aeefc84afe1c50e1
CPU Threads: 4; OS Version: Windows 6.19; UI Render: default; Layout Engine: new;
Locale: en-US (en_US); Calc: group

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