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During IBD, if LoadingBlocks() is true (e.g. during a chainstate rebuild after a crash), the node rejects incoming headers from peers. The GUI has headers loaded from the block index on disk, but bestHeaderDate becomes stale over time.
After ~4 hours (HEADER_HEIGHT_DELTA_SYNC * nPowTargetSpacing), the time-based heuristic in modaloverlay.cpp considers headers as "not synced" and falls into the else branch, displaying "Unknown" for both blocks remaining and estimated time. Meanwhile, UpdateHeaderSyncLabel() computes a percentage that rounds up to 100.0%, creating a contradictory display: "Unknown. Syncing Headers (942188, 100.0%)". Please read issue #65 for more context.
This patch truncates the percentage to one decimal place instead of rounding, so it only shows 100.0% when headers are truly up to date. The same fix is applied to
UpdateHeaderPresyncLabel() for consistency.
Fixes #65 .
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