XS_ENABLE_MODEL_EDITING_IN_GA
Category in Advanced options dialog: Modeling properties
Use this advanced option to control whether it is possible to edit a model while having a general arrangement (GA) drawing open. The default value of the advanced option is TRUE, which means that editing the model is possible. Set to FALSE to prevent the editing.
This advanced option is user specific and the setting is saved in options.bin under the user folder, for example, in C:\Users\<user>\AppData\Local\Trimble\Tekla Structures\<version>\UserSettings. Restart Tekla Structures to activate the new value.