LogMetal: Display: Loaded a text shader (will be slower to load)

Hello everyone,I’m running my project in IPHONEX, and LOG shows a lot of Loaded a text shader (will be slower to load).What happened?

[2019.07.31-07.48.52:426][  0]LogInit: Display: Game Engine Initialized.
[2019.07.31-07.48.52:427][  0]LogInit: Display: Starting Game.
[2019.07.31-07.48.52:427][  0]LogNet: Browse: /Game/Maps/Menu/VR_DemoStart?Name=Player
[2019.07.31-07.48.52:429][  0]LogLoad: LoadMap: /Game/Maps/Menu/VR_DemoStart?Name=Player
[2019.07.31-07.48.52:559][  0]LogUObjectHash: Compacting FUObjectHashTables data took   4.41ms
[2019.07.31-07.48.55:641][  0]LogMetal: Display: Got a bulk data texture, with 1 mips
[2019.07.31-07.48.55:641][  0]LogMetal: Display: Got a bulk data texture, with 1 mips
[2019.07.31-07.48.55:641][  0]LogMetal: Display: Got a bulk data texture, with 1 mips
[2019.07.31-07.48.55:641][  0]LogMetal: Display: Got a bulk data texture, with 1 mips
[2019.07.31-07.48.55:641][  0]LogMetal: Display: Got a bulk data texture, with 1 mips
[2019.07.31-07.48.55:641][  0]LogMetal: Display: Got a bulk data texture, with 1 mips
[2019.07.31-07.48.55:641][  0]LogMetal: Display: Got a bulk data texture, with 1 mips
[2019.07.31-07.48.55:641][  0]LogMetal: Display: Got a bulk data texture, with 1 mips
[2019.07.31-07.48.55:641][  0]LogMetal: Display: Got a bulk data texture, with 1 mips
[2019.07.31-07.48.55:700][  0]LogAIModule: Creating AISystem for world VR_DemoStart
[2019.07.31-07.48.55:700][  0]LogLoad: Game class is 'VRMenuMdoe_C'
[2019.07.31-07.48.55:700][  0]LogStreaming: Display: ULevelStreaming::RequestLevel(/Game/Maps/Menu/VR_Level1_MenuScene) is flushing async loading
[2019.07.31-07.48.55:791][  0]LogWorld: Bringing World /Game/Maps/Menu/VR_DemoStart.VR_DemoStart up for play (max tick rate 0) at 2019.07.31-15.48.55
[2019.07.31-07.48.55:793][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.55:793][  0]LogWorld: Bringing up level for play took: 0.005907
[2019.07.31-07.48.55:794][  0]LogGameMode: Display: Match State Changed from EnteringMap to WaitingToStart
[2019.07.31-07.48.55:794][  0]LogGameState: Match State Changed from EnteringMap to WaitingToStart
[2019.07.31-07.48.55:794][  0]LogGameMode: Display: Match State Changed from WaitingToStart to InProgress
[2019.07.31-07.48.55:797][  0]LogUMG: Display: Widget Class LoadingSkin_UMG_C - Loaded Fast Template.
[2019.07.31-07.48.55:797][  0]LogUMG: Display: Widget Class Skin_SkinBase_C - Loaded Fast Template.
[2019.07.31-07.48.55:798][  0]LogUMG: Display: Widget Class Menu_UMG_C - Loaded Fast Template.
[2019.07.31-07.48.55:810][  0]LogUMG: Display: Widget Class EnterGame_UMG_C - Loaded Fast Template.
[2019.07.31-07.48.55:811][  0]LogUMG: Display: Widget Class Annunciatorboards_UMG_C - Loaded Fast Template.
[2019.07.31-07.48.55:811][  0]LogUMG: Display: Widget Class XboxOne_GamePad_UMG_C - Loaded Fast Template.
[2019.07.31-07.48.55:811][  0]LogUMG: Display: Widget Class MainMenuGamePad_UMG_C - Loaded Fast Template.
[2019.07.31-07.48.55:812][  0]r.Mobile.TonemapperFilm = "1"
[2019.07.31-07.48.55:812][  0]r.ScreenPercentage = "75"
[2019.07.31-07.48.55:813][  0]t.MaxFPS = "120"
[2019.07.31-07.48.55:816][  0]LogGameState: Match State Changed from WaitingToStart to InProgress
[2019.07.31-07.48.55:816][  0]LogLoad: Took 3.387077 seconds to LoadMap(/Game/Maps/Menu/VR_DemoStart)
[2019.07.31-07.48.55:816][  0]LogStreaming: Display: Suspending async loading (1)
[2019.07.31-07.48.55:995][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.56:123][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.56:303][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.56:422][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.56:579][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.56:673][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.56:782][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.56:902][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.57:054][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.57:054][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.57:054][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.57:183][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.57:366][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.57:489][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.57:489][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.57:489][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.57:489][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.57:628][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.57:628][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.57:628][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.57:628][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.57:770][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.57:770][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.57:867][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.57:867][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.57:963][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.58:143][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.58:272][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.58:428][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.58:524][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.58:524][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.58:675][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.58:677][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.58:809][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.58:809][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.58:958][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.59:134][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.59:278][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.59:410][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.59:503][  0]LogMetal: Display: Loaded a text shader (will be slower to load)
[2019.07.31-07.48.59:503][  0]LogMetal: Display: Loaded a text shader (will be slower to load)