QGIS » QGIS Application

2.8.7 and prior versions
1. Create a style for a vector layer
2. Set style as default

2.8.9 onward
1. copy qgis.qmldb file (2.8.7 -) to 2.8.9+
2. Open same vector layer, no style has been applied

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2.8.7 and prior versions
1. Create a style for a vector layer
2. Save QGIS project

2.8.9 onward
1. Open QGIS project (style loaded fine)
2. Set style as deafult
3. Reopen QGIS: style not loaded

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So I can only set default styles in QGIS 2.8.9 if I create them in the current version

2.8.9 onward
1. Create a style for a vector layer
2. Set style as default
3. Reopen QGIS and load the vector
4. Default style loaded

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I have to say, recreate styles for 150 layers will be a pain....